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%I #19 Nov 14 2014 13:08:43
%S 1,2,1,2,10,2,1,2,118,19,519,2,635,370,829,1333,8454,17315,3599,15307,
%T 423769,852006,495431,2,2425755,2121070,3192295,1614598,35685686,
%U 10081687,735961,12902173,216093318,151123623,5270424935,39937013,22884337,7281379334
%N a(n) = core(Sum_{i=0,...,n} core(binomial(n,i))), where core(n) = A007913(n).
%t a7913[n_]:=a7913[n]=Times@@(#[[1]]^Mod[#[[2]],2])&[Transpose[FactorInteger[n]]];
%t Map[a7913[Total[Map[a7913,Binomial[#,Range[0,#]]]]]&,Range[0,50]] (* _Peter J. C. Moses_, Oct 28 2014 *)
%o (PARI) a(n) = core(sum(i=0, n, core(binomial(n,i)))); \\ _Michel Marcus_, Nov 13 2014
%Y Cf. A007913, A248470, A248473, A249388.
%K nonn
%O 0,2
%A _Vladimir Shevelev_, Oct 28 2014
%E More terms from _Peter J. C. Moses_, Oct 28 2014