cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A108603 Numbers n such that n! can be written as the product of smaller distinct factorials in more than one way.

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%I A108603 #5 Mar 30 2012 18:34:58
%S A108603 10,720,1440,17280,34560
%N A108603 Numbers n such that n! can be written as the product of smaller distinct factorials in more than one way.
%C A108603 No other terms < 65000. This is a subsequence of A075082. All known members of the sequence exploit the fact that 6! = 5! * 3! (they must have 6! without either 5! or 3! in one solution). Factorizations: 10 = 2*5; 720 = 2^4 * 3^2 * 5; 1440 = 2^5 * 3^2 * 5; 17280 = 2^7 * 3^3 * 5; 34560 = 2^8 * 3^3 * 5;
%e A108603 34560! = 34559! * 6! * 4! * 2! = 34559! * 5! * 4! * 3! * 2!
%Y A108603 Cf. A075082, A000142.
%K A108603 nonn,more
%O A108603 1,1
%A A108603 _Jud McCranie_, Jun 13 2005