login
A131053
2
1, 1, 2, 2, 2, 3, 2, 6, 3, 4, 3, 6, 13, 4, 5, 3, 12, 13, 24, 5, 6, 4, 12, 34, 24, 40, 6, 7, 4, 20, 34, 80, 40, 62, 7, 8, 5, 20, 70, 80, 166, 62, 91, 8, 9
OFFSET
1,3
COMMENTS
Row sums = (2^n - 1): (1, 3, 7, 15, ...).
Left border = A004526: (1, 1, 2, 2, 3, 3, ...).
FORMULA
A000012 * A131047 as infinite lower triangular matrices.
EXAMPLE
First few rows of the triangle:
1;
1, 2;
2, 2, 3;
2, 6, 3, 4;
3, 6, 13, 4, 5;
3, 12, 13, 24, 5, 6;
4, 12, 34, 24, 40, 6, 7;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jun 12 2007
STATUS
approved