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%I #5 Oct 15 2013 22:30:59
%S 3,2,1,2,2,2,4,2,2,6,5,4,10,4,2,8,10,6,12,4,6,18,10,4,14,14,6,10,23,
%T 20,22,10,18,22,10,18,34,26,15,18,24,14,32,14,10,42,28,12,28,18,12,32,
%U 34,14,25,26,42,54,30,14,58,42,22,24,28,36,60,38,20,34,44,26,70,42,20,42
%N Number of binomial coefficients C[n,j] with j=0...n that are divisible by C[n,2].
%F a(n)=Cardinality{j|Mod[C(n, j), C(n, 2)]=0, j=0..n}; For n=1 Mod[1, 0] does not exist.
%e The relevant residues are for n=16: {1, 16, 0, 80, 20, 48, 88, 40, 30, 40, 88, 48, 20, 80, 0, 16, 1}, a(16)=2; n=227: only with 6 nonzero residues: {1, 227, [111 zero], 454, 454, [111 zeros], 227, 1}
%Y A060430, A014070.
%K nonn
%O 2,1
%A _Labos Elemer_, Apr 12 2001
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