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%I #8 Apr 17 2017 09:02:53
%S 0,0,1,0,5,8,12,20,49,64,304,672,1204,2648,3852,9320,18297,32960,
%T 75472,146392,304920,577336,1211144,2034072,4801892,7637392,18795944,
%U 33811680,71566612,139144320,285508328,569229920,1069209737,2314296064,4167725024,8567738280,16894013736,33135107200,68279466472,121133055024
%N Row sums of A285118: a(n) = Sum_{k=1..(n-1)} (C(n-1,k-1) bitwise-and C(n-1,k)), a(0) = a(1) = 0.
%H Antti Karttunen, <a href="/A285115/b285115.txt">Table of n, a(n) for n = 0..256</a>
%F a(0) = a(1) = 0, and for n > 1, a(n) = Sum_{k=1..(n-1)} C(n-1,k-1) AND C(n-1,k), where C(n,k) is a binomial coefficient & AND is bitwise-AND (A004198).
%F a(n) = A285113(n) - A285114(n).
%F a(n) = A000079(n) - A285113(n) = (A000079(n) - A285114(n))/2.
%t a[n_]:=If[n<2, 0, Sum[BitAnd[Binomial[n - 1,k - 1], Binomial[n - 1, k]], {k, n - 1}]]; Table[a[n], {n, 0, 100}] (* _Indranil Ghosh_, Apr 16 2017 *)
%o (PARI) A285115(n) = if(n<2,0,sum(k=1,(n-1),bitand(binomial(n-1,k-1),binomial(n-1,k))));
%o (Scheme)
%o (define (A285115 n) (add A285118 (A000217 n) (+ -1 (A000217 (+ 1 n)))))
%o (define (add intfun lowlim uplim) (let sumloop ((i lowlim) (res 0)) (cond ((> i uplim) res) (else (sumloop (+ 1 i) (+ res (intfun i)))))))
%Y Cf. A000079, A004198, A007318, A285113, A285114, A285118.
%K nonn
%O 0,5
%A _Antti Karttunen_, Apr 16 2017
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