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A271345
Integers n such that (n-1)! is divisible by n^3.
1
1, 12, 18, 20, 24, 27, 28, 30, 32, 35, 36, 40, 42, 44, 45, 48, 49, 50, 52, 54, 55, 56, 60, 63, 64, 65, 66, 68, 70, 72, 75, 76, 77, 78, 80, 81, 84, 85, 88, 90, 91, 92, 95, 96, 98, 99, 100, 102, 104, 105, 108, 110, 112, 114, 115, 116, 117, 119, 120, 121, 124, 125, 126, 128, 130, 132, 133, 135
OFFSET
1,2
COMMENTS
Integers n such that A000142(n-1) is divisible by A000578(n).
Obviously, all terms are nonprime.
For n > 1, members of this sequence are short leg of more than one Pythagorean triangle.
EXAMPLE
12 is a term because 11! is divisible 12^3.
PROG
(PARI) lista(nn) = for(n=1, nn, if((n-1)! % (n^3) == 0, print1(n, ", ")));
CROSSREFS
KEYWORD
nonn
AUTHOR
Altug Alkan, Apr 04 2016
STATUS
approved