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Row sums of triangle A137680.
3

%I #7 Sep 19 2024 07:19:57

%S 1,2,4,10,23,56,132,316,752,1793,4272,10183,24266,57833,137828,328475,

%T 782827,1865651,4446255,10596406,25253567,60184809,143433647,

%U 341833954,814665553,1941527332,4627086990,11027366781,26280642313,62632555360,149267165702

%N Row sums of triangle A137680.

%C Partial sums of A137681 prefaced with a 1 = left border of triangle A137680: (1, 1, 3, 7, 17, 40, 96, 228, ...) = A137682. A variation of A137681 = column 2 of triangle A137680: (1, 0, 2, 4, 10, 23, 56, 132, 316, ...).

%e a(4) = 10 = sum of row 4 terms of triangle A137680: (7 + 2 + 0 + 1).

%Y Cf. A137680, A137682.

%K nonn

%O 1,2

%A _Gary W. Adamson_, Feb 05 2008