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%I #15 Jul 14 2019 17:58:01
%S 1,1,1,2,2,6,6,8,12,30,30,36,36,72,96,128,128,180,180,300,300,600,600,
%T 864,1152,2304,2688,4368,4368,5376,5376,6144,6144,13056,16320,19440,
%U 19440,38880,43200,48000,48000,64000,64000,100800,133056,278784,278784
%N Number of square divisors of n!.
%H Amiram Eldar, <a href="/A055993/b055993.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A046951(n!) = A000005(A055772(n)) = A000005(A000188(A000142(n))).
%t Table[Count[Divisors[n!], d_ /; IntegerQ@ Sqrt@ d], {n, 30}] (* _Michael De Vlieger_, Feb 05 2017 *)
%o (PARI) a(n) = sumdiv(n!, d, issquare(d)); \\ _Michel Marcus_, Dec 26 2013
%Y Cf. A000142, A000005, A046951, A055772, A000188.
%K nonn
%O 1,4
%A _Labos Elemer_, Jul 21 2000
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