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%I #13 Feb 19 2017 07:11:22
%S 1,1,1,1,1,2,1,1,2,4,1,2,2,2,2,2,1,2,1,2,2,2,1,2,4,4,8,8,4,6,2,2,2,4,
%T 2,4,4,4,2,4,2,2,2,2,8,12,4,8,8,8,8,8,4,6,2,2,2,3,2,3,3,3,4,4,2,4,2,4,
%U 4,4,1,2,2,2,4,4,8,12,2,4,12,12,4,4,8,12,12,12,4,6,8,12,12,12,8,16,8,8,6
%N Number of square divisors of central binomial coefficients.
%H Michel Marcus, <a href="/A056061/b056061.txt">Table of n, a(n) for n = 1..120</a>
%F a(n) = A046951(A001405(n)) = A000005(A000188(A001405(n)).
%e n=27: binomial(27,1) = 20058300, its largest square-divisor is 900=30^2 so a(27) = tau(30) = 8.
%t Table[Count[Divisors@ Binomial[n, Floor[n/2]], d_ /; IntegerQ@ Sqrt@ d], {n, 0, 84}] (* _Michael De Vlieger_, Feb 18 2017 *)
%o (PARI) a(n) = sumdiv(binomial(n, n\2), d, issquare(d)); \\ _Michel Marcus_, Feb 19 2017
%Y Cf. A001405, A046951, A000005, A000188, A056056, A056057, A056058, A056059, A056060.
%K nonn
%O 1,6
%A _Labos Elemer_ Jul 26 2000
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