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A131899
1
1, 2, 3, 3, 2, 5, 4, 2, 3, 7, 5, 2, 3, 4, 9, 6, 2, 3, 4, 5, 11, 7, 2, 3, 4, 5, 6, 13, 8, 2, 3, 4, 5, 6, 7, 15, 9, 2, 3, 4, 5, 6, 7, 8, 17, 10, 2, 3, 4, 5, 6, 7, 8, 9, 19
OFFSET
0,2
COMMENTS
Row sums = A052905: (1, 5, 10, 16, 23, ...)
FORMULA
A002260 + A131821 - A000012 as infinite lower triangular matrices.
EXAMPLE
First few rows of the triangle:
1;
2, 3;
3, 2, 5;
4, 2, 3, 7;
5, 2, 3, 4, 9;
6, 2, 3, 4, 5, 11;
7, 2, 3, 4, 5, 6, 13;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jul 25 2007
STATUS
approved