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A131901
1
1, 2, 2, 3, 5, 3, 4, 7, 7, 4, 5, 9, 9, 9, 5, 6, 11, 11, 11, 11, 6, 7, 13, 13, 13, 13, 13, 7, 8, 15, 15, 15, 15, 15, 15, 8, 9, 17, 17, 17, 17, 17, 17, 17, 9, 10, 19, 19, 19, 19, 19, 19, 19, 19, 10
OFFSET
1,2
COMMENTS
Row sums = A084849: (1, 4, 11, 22, 37, ...).
FORMULA
2*A002024 - A131821 as infinite lower triangular matrices.
EXAMPLE
First few rows of the triangle:
1;
2, 2;
3, 5, 3;
4, 7, 7, 4;
5, 9, 9, 9, 5;
6, 11, 11, 11, 11, 6;
7, 13, 13, 13, 13, 13, 7;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jul 26 2007
STATUS
approved