A325436 - OEIS

A325436

Numbers m such that m! / sigma(m) is not an integer.

2, 3, 4, 9, 16, 25, 64, 289, 729, 1681, 2401, 3481, 4096, 5041, 7921, 10201, 15625, 17161, 27889, 28561, 29929, 65536, 83521, 85849, 146689, 262144, 279841, 458329, 491401, 531441, 552049, 579121, 597529, 683929, 703921, 707281, 734449, 829921, 1190281

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OFFSET

1,1

COMMENTS

Numbers A053182(n)^2 are terms for n >= 1.

Complement of A325435.

Union of the number 3 and numbers m from A023194 (sigma(m) = prime).

LINKS

Table of n, a(n) for n=1..39.

PROG

(Magma) [n: n in [1..10000] | not IsIntegral(Factorial(n)/&+[d: d in Divisors(n)])]

(PARI) isok(n) = ((n! % sigma(n)) != 0); \\ Michel Marcus, Apr 26 2019