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Triangle read by rows, n-th row = (n-2)-th row appended to the beginning of (n-1)-th row, + n.
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%I #3 Mar 30 2012 17:25:28

%S 1,1,2,1,1,2,3,1,2,1,1,2,3,4,1,1,2,3,1,2,1,1,2,3,4,5,1,2,1,1,2,3,4,1,

%T 1,2,3,1,2,1,1,2,3,4,5,6,1,1,2,3,1,2,1,1,2,3,4,5,1,2,1,1,2,3,4,1,1,2,

%U 3,1,2,1,1,2,3,4,5,6,7

%N Triangle read by rows, n-th row = (n-2)-th row appended to the beginning of (n-1)-th row, + n.

%C There are (1, 2, 4, 7, 12,...) terms per row where (0, 0, 1, 2, 4, 7, 12,...) = A000071 = Fibonacci numbers - 1.

%C Row sums = A001924: (1, 3, 7, 14, 26, 46,...)

%F Triangle read by rows, n-th row = (n-2)-th row appended to the beginning of (n-1)-th row, + n.

%e First few rows of the triangle are:

%e 1;

%e 1, 2;

%e 1, 1, 2, 3;

%e 1, 2, 1, 1, 2, 3, 4;

%e 1, 1, 2, 3, 1, 2, 1, 1, 2, 3, 4, 5;

%e 1, 2, 1, 1, 2, 3, 4, 1, 1, 2, 3, 1, 2, 1, 1, 2, 3, 4, 5, 6;

%e ...

%e Row 4 = (1, 2, 1, 1, 2, 3, 4) = (row 2 appended to row 3, + 4); = (1, 2) appended to (1, 1, 2, 3), then 4.

%Y Cf. A000071, A001924.

%K nonn,tabf

%O 1,3

%A _Gary W. Adamson_, Jun 22 2008