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Statement

Display (5) of the paper (p. 27) writes the product of nn consecutive integers as

∏i=1n(x+i)=∏1piαi(x,n)∏2qjβj(x,n),(5)\prod_{i=1}^{n}(x+i)=\prod\nolimits_1 p_i^{\alpha_i(x,n)}\prod\nolimits_2 q_j^{\beta_j(x,n)}, \tag{5}

where ∏1\prod_1 runs over the primes pi≤np_i\le n and ∏2\prod_2 over the primes qj>nq_j>n, and display (6) names the family of all these exponents, {αi(x,n),βj(x,n)}\{\alpha_i(x,n),\beta_j(x,n)\}.

On p. 27 Erdős first remarks that it is easy to see that for every nn there are infinitely many xx for which the αi(x,n)\alpha_i(x,n) are all distinct, and that surely the αi(x,n)\alpha_i(x,n) are subject only to the condition αi(x,n)≥αi(n)\alpha_i(x,n)\ge\alpha_i(n), the exponent of pip_i in n!n! (he did not carry out the details). He does not believe that, for large nn, all the exponents (6) can be distinct, and states:

Conjecture (p. 27). For every kk there is an n0n_0 such that for n>n0n>n_0 at least kk of the exponents (6) equal 11.

The print states no condition on xx; the conjecture is read as holding for every xx for which (5) is a product of positive integers. Erdős calls the conjecture "no doubt unattainable at present" (p. 27). The paper gives no proof or evidence for it.

Source. P. Erdős, Miscellaneous problems in number theory, Proceedings of the Eleventh Manitoba Conference on Numerical Mathematics and Computing (Winnipeg, Man., 1981), Congr. Numer. 34 (1982), 25--45; displays (5) and (6) and the conjecture on p. 27. The edition read is identified on the source card.

Read depth. Claims checked: the passage was read clause by clause on the page image. There is no proof to check.

Dependencies

None. The weaker conjecture with k=1k=1 is the Erdős--Selfridge conjecture of p. 28, recorded on its own page.

Bears on

  • Problem 137: an exponent equal to 11 is a prime dividing the product exactly once, so the conjecture with k=1k=1 would make the product of nn consecutive positive integers never powerful for every n>n0n>n_0; it would leave the problem open for 3≤n≤n03\le n\le n_0. The paper poses the conjecture and records no result on it.