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A131050
(1/5) * (A007318^4 - A007318^(-1)).
4
1, 3, 2, 13, 9, 3, 51, 52, 18, 4, 205, 255, 130, 30, 5, 819, 1230, 765, 260, 45, 6, 3277, 5733, 4305, 1785, 455, 63, 7, 13107, 26216, 22932, 11480, 3570, 728, 84, 8
OFFSET
1,2
COMMENTS
Row sums = powers of 5: (1, 5, 25, 125, ...).
Left border = A015521: (1, 3, 13, 51, 205, 819, ...).
FORMULA
Let P = Pascal's triangle, A007318. Then A131050 = (1/5) * (P^4 - 1/P); deleting the right border of zeros.
EXAMPLE
First few rows of the triangle:
1;
3, 2;
13, 9, 3;
51, 52, 18, 4;
205, 255, 130, 30, 5;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Jun 12 2007
STATUS
approved