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A222060
Triangle read by rows: coefficients of harmonic-geometric polynomials.
2
0, 0, 1, 0, 1, 3, 0, 1, 9, 11, 0, 1, 21, 66, 50, 0, 1, 45, 275, 500, 274, 0, 1, 93, 990, 3250, 4110, 1764, 0, 1, 189, 3311, 17500, 38360, 37044, 13068, 0, 1, 381, 10626, 85050, 287700, 469224, 365904, 109584, 0, 1, 765, 33275, 388500, 1904574, 4667544, 6037416, 3945024, 1026576, 0, 1, 1533, 102630, 1705250, 11651850, 40266828, 76839840, 82188000, 46195920, 10628640
OFFSET
0,6
FORMULA
The n-th polynomial is Sum_{k=0..n} Stirling2(n,k)*|Stirling1(k+1,2)|*x^k.
EXAMPLE
Triangle begins:
[0]
[0, 1]
[0, 1, 3]
[0, 1, 9, 11]
[0, 1, 21, 66, 50]
[0, 1, 45, 275, 500, 274]
[0, 1, 93, 990, 3250, 4110, 1764]
[0, 1, 189, 3311, 17500, 38360, 37044, 13068]
[0, 1, 381, 10626, 85050, 287700, 469224, 365904, 109584]
...
CROSSREFS
Row sums give A222058. See A222057 for another version.
Sequence in context: A152150 A136239 A225443 * A256549 A211608 A058175
KEYWORD
nonn,tabl
AUTHOR
N. J. A. Sloane, Feb 08 2013
STATUS
approved