A141289 Triangle read by rows, n-th row = (n-2)-th row appended to the beginning of (n-1)-th row, + n.

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

Offset: 1

Author

Gary W. Adamson, Jun 22 2008

Keywords

• nonn
• tabf

Comments

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

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

Examples

			First few rows of the triangle are:
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, 1, 2, 3, 1, 2, 1, 1, 2, 3, 4, 5, 6;
...
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.
		

Crossrefs

Cf. A000071, A001924.

Formula

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