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Prime Dilation and Alternating Cubes for the Binary Totient Series
This page uses the notation of the binary totient sketch: and , so with . If with integers , then for every . The arguments below are Plasma AI's, author-recorded, and have not received independent review.
The mechanism tested here is the reduction by which Tao and Teräväinen prove that is irrational, [[../library/arithmetic_functions/tao_2025_quantitative_correlations_problems_prime_factors_consecutive/_index|Section 5 of their correlation paper]] (arXiv:2512.01739v2), the result recorded for Problem 69. Their argument has three moves: a prime dilation of the shift tail, using (their (5.1)--(5.3)); an alternating sum over a cube of primes that cancels the first shifts identically (their (5.4)--(5.8)); and a variance argument that writes the remaining phase as a sum of small, nearly independent prime contributions (their (5.12)--(5.21), with their Theorem 3.1 for the very large primes). Only the shift bookkeeping of the second move is reused below, and it is elementary; no theorem of the source is consumed. The totient analogues of the first two moves are exact. A common-divisor normalization improves their coefficients, but the third move still needs an unproved phase estimate. The results below delimit specific attempted constructions; they do not exclude other decompositions or resolve Problem 249. Here means logarithm to base two and means natural logarithm; the source instead uses for iterated natural logarithms.
The dilation identity
Lemma 1. For a prime and an integer ,
If , then $q\sum_{h\ge1}\varphi(pN+ph)2^{-h}\equiv q,\delta_p(N) \pmod 1$.
Proof. For every , when and when ; that is, . Apply this to and sum with weights ; both series converge absolutely. The congruence follows from .
The error is weighted by a totient value, unlike the source's indicator error. Two bounds make the difference quantitative. First, for ,
since the -th prime divisor of is at least and . Second, the least with satisfies , so
Hence forces ; for this means . When (the case ), the terms are and , so this threshold has the right order. For the source's error in (5.3) is at most in the corresponding case. When the error contains the term , which can be as large as ; the source's averaged treatment of that event is discussed under the parameter ranges below.
The alternating cube
Proposition 2. Let and let be integers such that are distinct primes for all . Put and . Let satisfy for every , and put and
Then for , and
If , then $q\sum_{h>K}\Delta_h(n)2^{-h}\equiv q\sum_\epsilon(-1)^{|\epsilon|}\delta_{p_\epsilon}(N_\epsilon)\pmod1$.
Proof. Since , Lemma 1 at , multiplied by and summed, gives the displayed identity once the terms are removed. For , does not involve ; pairing with the vector that differs from it only in coordinate gives equal arguments and opposite signs, so . The congruence follows from .
The cancellation for holds for every function in place of ; only the right-hand side uses multiplicativity. The congruences are the source's single-power conditions (5.5). Requiring instead means , the case of the pointwise upper bound after Lemma 1.
The identity is exact, and its phase is also a function of the target. Since , the left side is congruent modulo one to $\sum_\epsilon(-1)^{|\epsilon|}\bigl((p_\epsilon-1){2^{N_\epsilon}S} +\delta_{p_\epsilon}(N_\epsilon)\bigr)$, unconditionally. An estimate for its phase is therefore equally a statement about the binary digits of at the positions . This is the cube counterpart of the one-window reformulation in the sketch.
A common-divisor normalization
Let be any positive common divisor of the . Dividing Proposition 2 by is compatible with rationality, since every is an integer. Thus implies
Also is an integer for every . Indeed, writing with gives .
Proposition 2a (weights for the prescribed cube pairings). Suppose nonzero rational weights are required to cancel separately at each of the paired equal arguments used in Proposition 2, for every . Then for one rational . The corresponding coefficients on are integers exactly when
Proof. Each prescribed pairing requires . Connecting vertices by coordinate flips gives the asserted weights. If all are integers, a Bezout combination of the shows that their gcd times is integral. The converse follows because that gcd divides each .
Consequently gives the largest common normalization within this class of integer tail coefficients. For example, , gives the prime vertices and . The normalized tail weights, in that order, are . This saves a factor six. It does not rule out other pairings, cancellations between different levels, or using extra divisibility of the tail integers. For instance is always even for under rationality, giving a further fixed factor two.
An averaged estimate and its parameter cost
Put and . Suppose , , and is divisible by every but by none of their squares. Let be the nonempty set of integers in in a single class modulo satisfying Proposition 2, and put and . Expectations below are uniform on , and .
Proposition 2b (complete error bound). For integers and , define
If , then
Proof. Write the members of as for consecutive integers . Then runs through all residues modulo in a cycle, since . For each , the event has probability at most . The union of these events for all vertices and has probability at most .
Off this exceptional event, the complete positive error satisfies
The complete signed tail beyond , divided by and multiplied by , is bounded absolutely by
Use (1), off the exceptional event, and the bound two for the difference of two unit complex numbers on that event. This gives (2). No infinite tail has been dropped.
One sufficient asymptotic regime, with and fixed, is
with integer , , and
Here , , and . Thus and ; both cutoffs are positive and of order . The range of the cube's vertices is , so . Also , , and . Substitution into (2) makes its right side . Cubes satisfying these hypotheses are required inputs; no existence claim for arbitrary growing is implicit in this estimate.
The regime is nonempty already with . Take two distinct odd primes in , put , and set for a fixed . Such pairs exist for all sufficiently large by the prime number theorem. The two congruences determine a class modulo , and (4) holds. This supplies an unbounded family for the error estimate, but no saving for its exponential average.
The normalization does not turn this absolute-bound method into a short window argument. Specifically,
The right side of (3) cannot tend to zero unless . This is a necessity for making that particular upper bound vanish, not a lower bound for the signed tail itself. Selected representatives with and estimates using signed cancellation are outside (6). From (4) and one also obtains
The condition likewise belongs to the exceptional-event bound in (2); it is not necessary for every use of (1). The source's choice does not meet it.
The remaining sufficient estimate is now exact: construct admissible parameters with for some fixed along an unbounded sequence. Equations (2)--(5) would contradict . Doing this for a set of containing a multiple of every positive integer would prove irrationality. No such saving is proved.
Where the variance step fails
The source obtains that estimate for from the identity , which writes its phase as with each prime piece on its core set (its (5.13) and (5.19)). For the phase has a different shape.
Proposition 3. Let and .
- If is odd, then for every integer the number is not an integer for all but integers .
- For every integer the number is an integer for all but integers .
Proof. The valuation is for . The additive function , the sums here running over odd primes , has mean . This uses Mertens' theorem in the classes for each fixed , and for the remaining classes the bound , which follows from the trivial count below and the Brun--Titchmarsh inequality above it. The variance bound is , by the same bound. In the prime-power form of Turán--Kubilius the mean and squared variance parameter differ from these prime sums by , since and . The inequality gives . The contribution exceeds for at most integers. Taking proves both parts; when is odd a term is an integer exactly when .
The all-integers estimate does not give an upper valuation bound on the averaging class. For example, a forced prime divisor congruent to one modulo a large power of two makes every corresponding totient divisible by that power. In particular Proposition 3(1) cannot show that the cube's remaining terms are non-integral, let alone bounded away from integers.
The lower valuation statement does transfer, including after the normalization by , by a direct argument. Suppose in addition to (4) that every prime factor of other than the is at most , where . For each vertex and each level separately, and each fixed , all but a proportion of the class satisfy
Here is a proof with its uniformity explicit. Choose a fixed integer so that . For odd primes define , let , and set
Every prime in this sum is coprime to . The single and pair divisibility probabilities over consecutive class members are and . Therefore
Fixed-modulus prime reciprocal sums give : write as the sum of the indicators , . The deleted primes contribute at most . Since , one has . Chebyshev now gives with the asserted exceptional proportion, uniformly in the vertex and shift.
Finally write with . Then
whose valuation is at least , since the primes counted by do not divide and in particular are different from . This proves (8).
By (7), the cancelled levels satisfy for, say, . Thus each cancelled coordinate was already integral for almost all class members. This is a statement for each coordinate, with a uniform exceptional proportion. It does not assert simultaneous integrality of all coordinates when grows. Nor does it locate the remaining phase: non-integrality is weaker than a fixed distance from , and even many non-integral terms can sum to an integer.
Two decompositions and their limits
The literal additive-prime identity used for fails for even modulo powers of two. For and distinct odd primes with ,
If , its product with is non-integral. Any expression for as a constant plus separate functions of the prime-power divisors of would have zero mixed difference on , contradicting (9). This excludes that exact additive identity on the four-point set. It excludes neither an approximate decomposition on a selected class nor terms involving several primes together.
The divisor expansion is exact, but its raw weighted pieces have size ; they do not come with the source's uniform bound. Integer pieces can be removed and other pieces can cancel, so this size calculation is an unmet estimate rather than an impossibility theorem for a regrouped divisor expansion.
A character expansion exposes a different cost. Already for the unnormalized case, on the stratum and for odd , put . The function on odd residues modulo has nonzero multiplicative-character coefficients, each of modulus , hence total coefficient mass . To see this, an imprimitive character has zero Gauss sum by pairing and . For a primitive character the square of the Gauss sum's modulus is : expansion of the square leaves only the residues and , on which its values are and . Divide by the group order . The odd part of is multiplicative, so each character composition is 1-bounded and multiplicative. The valuation stratum, the growing coefficient mass and the joint shifts still need control. This calculation is not a lower bound for every possible expansion.
The inspected Theorem 3.1 is a two-point estimate with either its real-valued equidistribution and prime-value assumptions (3.1)--(3.2), or its quantified non-pretentiousness assumption (3.3). Its scale parameter satisfies ; its progression modulus and shifts are for a sufficiently small absolute , and it omits a quantitatively bounded exceptional set of scales. A direct application to the full class here is outside that range: (4) gives and , whereas would be required. Removing a forced prime factor or using a different representation needs a new reduction, with its hypotheses checked afresh.
More fundamentally, no decomposition and moment comparison yielding a fixed saving for has been obtained from these inputs. The source uses small additive prime pieces before invoking its correlation theorem. Formula (9) blocks the literal additive identity; the divisor and character expansions above supply no replacement estimate. This is the precise remaining gap, not a theorem that all correlation approaches fail.
Exact cancellation by dilation designs
A different arrangement of dilations could cancel more levels by equal arguments. There is a window bound for this particular mechanism. Arithmetic progressions with different strides need not be disjoint or meet only once; their intersection period is essential.
Proposition 4 (bounded coincidence count). Consider lines , , with nonzero rational , positive integer strides , and integer offsets satisfying . Equal strides are required to have distinct offsets modulo that stride. On each line select any consecutive positive levels. For distinct strides put . Then the number of selected points on line that lie on no other line is at least
In particular, if for all pairs of distinct strides, there are at least unshared points in total. Their formal coefficients in are nonzero. If is an integer and a selected level exceeds , that coefficient is also non-integral.
Proof. Membership of in line requires . This congruence is either inconsistent or restricts to one residue modulo . It therefore has at most solutions in consecutive levels. Requiring the corresponding index on line to be positive can only remove solutions. Equal strides contribute none by the offset assumption. A union bound gives (10). Unshared points on different lines are distinct, and each retains its single nonzero coefficient.
The window restriction cannot be omitted. For , , , and , line 1 has two shared selected points and line 2 has three. There are only seven unshared pairs, fewer than . The two progressions share every positive multiple of six.
For the cube's distinct prime strides, . In regime (4), any block of levels meets the required window restriction. In particular, the block of (5) has while . It retains at least unshared points. Dividing all weights by does not change this count. Thus coincidences of arguments alone do not annihilate the normalized truncated expression as a formal linear combination.
This does not show that the values of that expression at the totient are nonzero or far from integers. Divisibility of a totient can turn a non-integral weight into an integer term, and distinct totient arguments can satisfy arithmetic relations. Equal-stride lines in one residue class are also outside the statement; they include the ordinary-tail combinations of the odd scalar-kernel route. Small strides with repeated intersections, other level selections and selected representatives outside (4) remain separate possibilities.
The favorable-window mechanism
The earlier conditional theorem for , [[../library/irrationality/pratt_2024_irrationality_prime_factor_series_under_prime/theorem_1_3|Pratt's Theorem 1.3]], uses a different mechanism. Its reduction takes with for all and prime for every such , so that the window values are known exactly; the rest of its tail is because is at most on the next shifts by construction and beyond. The totient analogue of the exact window is . Its discarded positive tail cannot satisfy the analogous smallness bound.
Proposition 5. For every there is such that no and satisfy both and .
Proof. By the bound of the dilation section, and since is nondecreasing on the positive integers, $\sum_{k>K}\varphi(N+k)2^{-k}\ge(N+1)2^{-K}/(1+\log_2(N+1)) \ge N2^{-K}/(2+\log_2N)$. So the second condition forces . The first condition gives for the Chebyshev function , and by the prime number theorem, so . These bounds are incompatible once is large.
A window with exact values and a discarded positive tail below therefore cannot use the cofactors . At a scale , the positive-tail lower bound also forces . An extension asking for one distinct prime linear form at every position of such a window would be outside the range of Pratt's [[../library/irrationality/pratt_2024_irrationality_prime_factor_series_under_prime/conjecture_1_2|quantitative prime tuples conjecture]], which covers at most forms with coefficients at most . It does not supply that longer prescription. This excludes neither a selected arithmetic subfamily with a different certificate nor weighted cancellation or another use of a prime-tuples hypothesis.
Standing and reopening
The retained construction consists of the exact dilation and cube identities, the common-divisor normalization, and the full averaged bound (2). The prescribed-pairing weight calculation, the limitation (6) of its absolute tail bound, the progression valuation estimate (8), the bounded coincidence count (10), and the positive-tail obstruction of Proposition 5 have their stated scopes only. These are Plasma AI's author-recorded arguments, without independent review or a native tier. The finite examples are exposed in the proofs; no numerical evidence is needed for their implications.
The construction stops at a specific unproved estimate: a fixed saving in for an admissible family. Neither the literal additive-prime identity nor the raw divisor or character expansion supplies it. The normalization saves a factor but does not remove the logarithmic window in this absolute-bound regime. Coincidences alone leave formal coefficients; they do not settle the phase at actual totient values. No impossibility claim for all weighted, correlation or selected-subfamily arguments follows.
A reopening input would be a decomposition with moment bounds yielding a fixed phase saving, a direct saving for the normalized phase, or a signed-tail estimate that avoids the bound (3). A new identity among the actual totient values could also use the surviving formal coefficients. The independent [[research/leads/totient_binary_series/integer_interpolation/two_depth_carries|odd scalar-kernel construction]] remains open: no vector family of cost is obtained here, and its equivalence with a phase criterion does not obstruct an arithmetic attack on it.
The external input and reading scope are as follows. Tao--Teräväinen's arXiv:2512.01739v2 is a preprint; its Theorem 3.1 was checked at statement depth, and the reduction in Sections 5.1--5.4 through Theorem 5.1 was followed in the held transcription. The later estimates proving that technical theorem are not imported. Pratt's arXiv:2409.15185 statement, Conjecture 1.2, Proposition 2.1 and the deduction of Theorem 1.3 from it were inspected in the held transcription; its prime-tuples hypothesis remains an assumption, and no proof of that hypothesis is claimed.
Proposition 3 uses the standard Turán--Kubilius and Brun--Titchmarsh inequalities. Their exact statements were checked in [[../library/unit_fractions/elsholtz_2013_counting_number_solutions_erdos_straus/_index|Elsholtz--Tao's arXiv:1107.1010v6]], Lemma A.2, p. 48, and (A.10), p. 49, including the page images. Their proofs remain external. The fixed-modulus reciprocal-prime asymptotic used there and in (8) is DLMF (27.11.9), version 1.2.8; only finitely many fixed moduli are used for each truncation. The prime number theorem used in Proposition 5 has the same disclosed external standing as on [[research/leads/totient_binary_series/integer_interpolation/phase_localization|the phase-localization page]]. These source statements and the elementary specializations above confer no independent acceptance on the target.