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A056596 Number of nonsquare divisors of n!. 1
0, 1, 3, 6, 14, 24, 54, 88, 148, 240, 510, 756, 1548, 2520, 3936, 5248, 10624, 14508, 29196, 40740, 60500, 95400, 191400, 242016, 338880, 529920, 674688, 912912, 1830192, 2327424, 4660224, 5523456, 7858176, 12152064, 16406592, 19576080 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
FORMULA
a(n) = d(n!) - A046951(n!)
a(n) = A027423(n) - A055993(n). - _Amiram Eldar_, Jul 16 2019
MATHEMATICA
Table[Count[Divisors[n!], d_ /; !IntegerQ@ Sqrt@ d], {n, 30}] (* _Amiram Eldar_, Jul 16 2019 after _Michael De Vlieger_ at A055993 *)
PROG
(Magma) [#[d:d in Divisors(Factorial(n))| not IsSquare(d)]:n in [1..36]]; // _Marius A. Burtea_, Jul 16 2019
CROSSREFS
Sequence in context: A291987 A200823 A093866 * A026341 A026271 A166212
KEYWORD
nonn
AUTHOR
_Labos Elemer_, Jul 21 2000
STATUS
approved

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Last modified June 17 15:52 EDT 2024. Contains 373462 sequences. (Running on oeis4.)