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%I #3 Mar 31 2012 13:21:02
%S 1,2,1,3,3,4,6,1,5,10,5,6,15,15,7,21,35,8,28,70,1,9,36,126,9,10,45,
%T 210,45,11,55,330,165,12,66,495,495,13,78,715,1287,14,91,1001,3003,15,
%U 105,1365,6435,16,120,1820,12870,1,17,136,2380,24310,17,18,153,3060,43758
%N Binomial coefficients binomial(m,2^k) where m>=1 and 1<=2^k<=m.
%C Provided m and k are given, the sequence index n is n=A001855(m)+k+1. Ordered by m as rows and k as columns the sequence forms a sort of a logarithmically distorted triangle. a(n) is odd if and only if A030308(n)=1.
%F a(n)=binomial(m,2^k), where m=max(j|A001855(j)<n) and k=n-1-A001855(m).
%e a(6)=4 since n=6 gives m=4, k=0 and so binomial(4,2^0)=4.
%e a(20)=70 since n=20 gives m=8, k=2 and so binomial(8,2^2)=70.
%Y Cf. A130068, A065040, A001855, A030308.
%K nonn
%O 1,2
%A _Hieronymus Fischer_, May 05 2007, Sep 10 2007
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