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A171239 Triangle read by rows extracted from convolution product (1,2,3,...) * A002865: (1,1,2,2,4,4,7,8,...)

%I A171239 #3 Mar 30 2012 17:25:35
%S A171239 1,1,2,2,2,3,2,4,3,4,4,4,6,4,5,4,8,6,8,5,6,7,8,12,8,10,6,7,8,14,12,16,
%T A171239 10,12,7,8,8,14,12,16,10,12,7,8,12,16,21,16,20,12,14,8,9,14,24,24,28,
%U A171239 20,24,14,10,9,10
%N A171239 Triangle read by rows extracted from convolution product (1,2,3,...) * A002865: (1,1,2,2,4,4,7,8,...)
%C A171239 Row sums = A058682 starting (1, 3, 7, 13, 23, 37, 58, 87,...).
%F A171239 Triangle read by rows, ascending diagonals of an array formed by the product of
%F A171239 (1,2,3,...) and (1,1,2,2,4,4,7,8,12,...).
%e A171239 The triangle = upward sloping diagonals of multiplication table:
%e A171239 .
%e A171239 1,..2,..3,..4,..5,..6,..7,...
%e A171239 1,..2,..3,..4,..5,..6,..7,...
%e A171239 2,..4,..6,..8,.10,.12,.14,...
%e A171239 2,..4,..6,..8,.10,.12,.14,...
%e A171239 ... First few rows of the triangle =
%e A171239 .
%e A171239 1;
%e A171239 1, 2;
%e A171239 2, 2, 3;
%e A171239 2, 4, 3, 4;
%e A171239 4, 4, 6, 4, 5;
%e A171239 4, 8, 6, 8, 5, 6;
%e A171239 7, 8, 12, 8, 10, 6, 7;
%e A171239 8, 14, 12, 16, 10, 12, 7, 8;
%e A171239 12, 16, 21, 16, 20, 12, 14, 8, 9;
%e A171239 14, 24, 24, 28, 20, 24, 14, 10, 9, 10;
%e A171239 21, 28, 36, 32, 35, 24, 28, 16, 18, 10, 11;
%e A171239 24, 42, 42, 48, 40, 42, 28, 32, 18, 20, 11, 12;
%e A171239 34, 48, 63, 56, 60, 48, 49, 32, 36, 20, 22, 12, 13;
%e A171239 41, 68, 72, 84, 70, 72, 56, 56, 36, 40, 22, 24, 13, 14;
%e A171239 ...
%Y A171239 Cf. A002865, A058682
%K A171239 nonn,tabl
%O A171239 1,3
%A A171239 _Gary W. Adamson_, Dec 05 2009