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Source. Sections 4.7 and 4.10–4.23, physical pp. 15–23 of the selected author version. The paper gives the package recipes and usually says to use previously constructed sets in construction order. This page fixes one such order and supplies the modulus check that the compressed notation leaves implicit.

The check is not a certificate for the missing second-1313 allocation at prime 3737. Rows that import the resulting 3535-package pool are conditional on the interface stated on the [[covering_systems/nielsen_2009_covering_system_smallest_modulus_40/primes_29_37|prime-3737 page]].

Exponent regions

For a regular leaf of modulus mm, put

σ(m)=(v2(m),v3(m),v5(m),…,v103(m)).(1)\sigma(m)=(v_2(m),v_3(m),v_5(m),\ldots,v_{103}(m)). \tag{1}

Every atomic factor fixes one coordinate of (1), and every upward arrow makes one coordinate an interval [e,∞)[e,\mathord\infty). Thus every finite syntax expression on the construction pages expands into a finite union of Cartesian products

I2×I3×⋯×I103,(2)I_2\times I_3\times\cdots\times I_{103}, \tag{2}

where each IpI_p is either 0{0}, a positive singleton, or a positive integer ray. Two regions meet exactly when their intervals meet on every prime coordinate. This is an exact unbounded calculation; no exponent cutoff is used.

The exceptional pools expand as follows. “Regions” counts the products (2) before equal products are merged. Comparing every pair with the same set of positive prime coordinates gives the last column.

Ordered poolPackagesRegionsIntersections
prime-1717: E1,…,E15E_1,\ldots,E_{15}151519419400
prime-1717: the two summands of E16E_{16}2221321300
prime-1717: combined E1,…,E16E_1,\ldots,E_{16}161640740700
prime-2929: first 2727 packages27271690169000
prime-2929: the three cross-completion pieces3312612600
prime-2929: final 2828 inputs28281823182300
prime-3131: high and low transforms28+2828+28648+648648+64800
prime-3131: final 3030 inputs30303119311900
prime-4141: first 3636 packages36362549254900
prime-4747: first 4141 packages414198098000
prime-5353: first 3232 packages323212812800
prime-6767: first 3939 packages3939818100
primes 71,73,79,8371,73,79,83: common first 47474747848400
prime-103103: first 4343 packages434314014000

These rows are obtained by applying (2) directly to the displayed formulas, including every summand and every blank. They are finite proofs of pairwise disjointness because an intersection would appear in the last column. The larger prime-4141 row includes the thirty multiplier-major choices from its T′′T'' pool. The prime-6767 row includes the partial fourth 25↑25^\uparrow and its 77-by-2525 rectangle. The prime-2929 row includes its partial 4949-by-1717 rectangle. Residue positions play no role in this test.

The fresh-prime block lemma

Let P=(A1,…,As)P=(A_1,\ldots,A_s) be an ordered pool whose signature sets are pairwise disjoint, and suppose prime qq occurs in none of them. If a target q↑q^\uparrow has hh already-covered regular inputs, take the first q−1−hq-1-h members of PP and put them in the other inputs in increasing-input order. More generally, to build rr copies, take the first r(q−1−h)r(q-1-h) members and split them into consecutive blocks.

Every new regular signature has positive qq-coordinate. It is therefore different from every old signature. Within one copy, the disjointness of the input block separates equal qq-levels; different levels have different qq-coordinates. Different copies use disjoint blocks. Hence adjoining the rr new packages preserves pairwise signature disjointness. The same proof applies to a selected input repeated through every level: its positive qq-coordinate separates it from the old pool, and injectivity of the old pool separates its leaves.

This lemma is applied only when qq is absent from the entire current pool. The deterministic schedules on the construction pages make that fact visible: each listed prime is new at the instant it is adjoined.

Exceptional unions

Four stages require more than the block lemma.

  1. At prime 2929, the partial 49↑49^\uparrow and partial 17↑17^\uparrow cover complementary rows and columns. Their six-cell rectangle uses the first six original packages with both selected prime coordinates. The three pieces are disjoint by the exact 126126-region row above.
  2. At prime 4141, the last composite package joins the selected final prime-1717 input beginning at exponent 22 to the first thirty multiplier-major members of (172)↑ ⁣⋅{1,5,7,35}{A1,…,A8}(17^2)^\uparrow\!\cdot\{1,5,7,35\}\{A_1,\ldots,A_8\}. Its 1717-exponent range separates it from the 00- and 11-exponent blocks; the 25492549-region comparison checks the internal unions.
  3. At prime 6767, the first three 25↑25^\uparrow packages use the first twelve base packages. The fourth uses packages 1313–1515 and the 7↑7^\uparrow cross-piece built from the selected missing prime-55 input of packages 11–66. The latter has v5≥2v_5\ge2, while the five direct prime-77 blocks have v5=0v_5=0 or 11.
  4. At primes 9797 and 101101, the first partial 97↑97^\uparrow covers inputs 11–9090. Each of the fifteen later copies contributes leaves only in its six open inputs, using a different consecutive block of the unshifted 9090-pool. Thus the old packages have v97=0v_{97}=0 and the fifteen new packages have v97>0v_{97}>0 with disjoint inner blocks. The ordinary 101101-node introduces only the fixed exponent v101=1v_{101}=1.

The partial prime-3737 package is the remaining exceptional small-prime input. The selected source does not specify the second-1313 input map needed to obtain its asserted 3535-package pool, and this compilation did not find a collision-free replacement. The later prime-5959 and prime-8989 schedules are therefore checked only conditionally on a complete, pairwise signature-disjoint ordered pool of 3535 packages with the stated coverage.

Deterministic later schedule

The following table records the initial certified pool and every subsequent block operation. A parenthesized number is the number of copies. “Mask” lists the precovered inputs; an empty entry means all q−1q-1 regular inputs are filled. Each operation uses the shortest required prefix, split into consecutive blocks.

Target poolInitial sizeOrdered operationsFinal size
4141363619(2)19(2), 37373939
434339394141 with mask {1}\{1\}4040
4747414129,31,37,41,4329,31,37,41,434646
535332327(5),13(3),31,37,41,43,23(2),47,11(5)7(5),13(3),31,37,41,43,23(2),47,11(5) with 1111-mask {1,2}\{1,2\}5252
595935∗35^*37(17)37(17) with mask {1,…,34}\{1,\ldots,34\}, then 41,43,47,5341,43,47,5356∗56^*
6161404043(20)43(20) with mask {1,…,40}\{1,\ldots,40\}6060
6767393937,41,11(4),43,47,23(2),13(4),53,19(3),17(5),29(2),31(2)37,41,11(4),43,47,23(2),13(4),53,19(3),17(5),29(2),31(2)6666
common 7171 pool474747,13(4),11(5),53,29(2),31(2),59,61,17(4),23(3),41,43,37(2),19(4)47,13(4),11(5),53,29(2),31(2),59,61,17(4),23(3),41,43,37(2),19(4)7979
8383797971,73,7971,73,798282
898956∗56^*59(28)59(28) with mask {1,…,56}\{1,\ldots,56\}, then 61,67,71,73,7961,67,71,73,7989∗89^*
97973939selected 4141 input applied to all 3939, then 53,59,61,67,71,73,79,43(2),83,89,4753,59,61,67,71,73,79,43(2),83,89,479090
101101909097(15)97(15) with mask {1,…,90}\{1,\ldots,90\}105105
103103434311(4),41,13(4),43,4711(4),41,13(4),43,47, then selected 1717 input applied to all 5454108108

At prime 6767, the five copies of 17↑17^\uparrow use mask {3,6,9,10,11}\{3,6,9,10,11\}; every other unshown mask in the table is empty. For the outer targets use the first 39,40,46,52,56,60,66,70,72,78,82,88,90,101,39,40,46,52,56,60,66,70,72,78,82,88,90,101, and 102102 packages at primes 41,43,47,53,59,61,67,71,73,79,83,89,97,101,10341,43,47,53,59,61,67,71,73,79,83,89,97,101,103, respectively. An asterisk marks a count whose local block arithmetic has been verified but whose starting pool is the unresolved prime-3737 interface.

Separation between target stages

Every regular package used inside the outer target at prime qq involves only regular primes smaller than qq. Thus every new leaf at that stage has greatest regular prime exactly qq. Different outer target stages cannot share a modulus. Within a stage, the region comparisons and block lemma give injectivity, subject at primes 5959 and 8989 to the starred input interface. Together with the earlier reusable-template certificate, this proves every unstarred regular-signature claim and proves the starred ones conditionally. It does not prove that every regular modulus in the full symbolic construction occurs once until the prime-3737 allocation is supplied.

This certificate concerns regular leaves. The finite-arrow lemma separates terminal moduli by fresh primes after regular injectivity has been proved.

Bears on. Problem 2.