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A157031 Triangle A054521 * A157019, where A054521 = an infinite lower triangular matrix and A157019 = a vector [1, 2, 2, 4, 2, 8, 2, 10, 8, ...].

%I A157031 #8 Feb 08 2022 23:16:48
%S A157031 1,1,3,3,9,3,19,7,21,13,51,7,87,17,39,51,175,11,239,21,169,111,415,15,
%T A157031 489,185,313,219,1017,15,1413,283,763,415,981,513,3057,839,1259,497,
%U A157031 4425,93,5605,893,1311,2259,7505,521,8267,1429,5473,3311,13821,1449,11135,4095
%N A157031 Triangle A054521 * A157019, where A054521 = an infinite lower triangular matrix and A157019 = a vector [1, 2, 2, 4, 2, 8, 2, 10, 8, ...].
%e A157031 a(4) = 3 = (1, 0, 1, 0) dot (1, 2, 2, 4) = (1 + 0 + 2 + 0), where (1, 0, 1, 0) equals row 4 of triangle A054521.
%p A157031 A157031 := proc(n)
%p A157031     add(A054521(n,k)*A157019(k),k=1..n) ;
%p A157031 end proc: # _R. J. Mathar_, Jul 21 2015
%Y A157031 Cf. A157019, A054521.
%K A157031 nonn
%O A157031 1,3
%A A157031 _Gary W. Adamson_ & _Mats Granvik_, Feb 21 2009