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Convolution of numbers of binary zeros and ones.
1

%I #10 Jul 16 2023 02:11:11

%S 0,1,1,3,2,6,6,11,8,15,15,25,21,29,29,41,33,44,43,61,53,66,67,89,76,

%T 88,85,107,96,112,112,139,119,135,130,161,144,165,166,205,180,197,191,

%U 227,209,235,237,283,250,267,256,295,269,295,293,343,308,329,319,365,339

%N Convolution of numbers of binary zeros and ones.

%H Reinhard Zumkeller, <a href="/A157793/b157793.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = Sum_{i=0..n} A023416(i)*A000120(n-i).

%t a[n_] := Sum[DigitCount[i, 2, 0]*DigitCount[n - i, 2, 1], {i, 0, n}]; Array[a, 100, 0] (* _Amiram Eldar_, Jul 16 2023 *)

%o (Haskell)

%o a157793 n = a157793_list !! n

%o a157793_list = f [head a023416_list] $ tail a023416_list where

%o f zs (x:xs) = (sum $ zipWith (*) zs a000120_list) : f (x:zs) xs

%o -- _Reinhard Zumkeller_, Mar 31 2015

%Y Cf. A000120, A023416.

%K nonn,base

%O 0,4

%A _Reinhard Zumkeller_, Mar 06 2009