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Eigentriangle, row sums = A002426
1

%I #5 Apr 18 2013 11:26:26

%S 1,2,1,2,2,3,4,2,6,7,8,4,6,14,19,18,8,12,14,38,51,42,18,24,28,38,102,

%T 141,102,42,54,56,76,102,282,393254,102,126,126,152,204,282,786,1107,

%U 646,254,306,2944,342,408,564,786,2214,3139

%N Eigentriangle, row sums = A002426

%C Row sums = A002426 starting with offset 1: (1, 3, 7, 19, 51, 141, 393,...).

%C Right border = A002426, left border = A007971

%C Sum of n-th row terms = rightmost term of next row.

%F Triangle read by rows, M*Q. M = an infinite lower triangular matrix with A007971 in every column: (1, 2, 2, 4, 8, 18, 42,...); and Q = a matrix with A002426 as the main diagonal and the rest zeros.

%e First few rows of the triangle =

%e 1;

%e 2, 1;

%e 2, 2, 3;

%e 4, 2, 6, 7;

%e 8, 4, 6, 14, 19;

%e 18, 8, 12, 14, 38, 51;

%e 42, 18, 24, 28, 38, 102, 141;

%e 102, 42, 54, 56, 76, 102, 282, 393;

%e 254, 102, 126, 126, 152, 204, 282, 786, 1107;

%e 646, 254, 306, 394, 342, 408, 564, 786, 2214, 3139;

%e ...

%e Row 3 = (4, 2, 6, 7) = termwise products of (4, 2, 2, 1) and (1, 1, 3, 7)

%K nonn,tabl

%O 1,2

%A _Gary W. Adamson_, Nov 29 2008