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A119830
Bi-diagonal inverse of (2n)!/(2k)!.
1
1, -2, 1, 0, -12, 1, 0, 0, -30, 1, 0, 0, 0, -56, 1, 0, 0, 0, 0, -90, 1, 0, 0, 0, 0, 0, -132, 1, 0, 0, 0, 0, 0, 0, -182, 1, 0, 0, 0, 0, 0, 0, 0, -240, 1, 0, 0, 0, 0, 0, 0, 0, 0, -306, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, -380, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -462, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -552, 1, 0, 0, 0, 0, 0, 0
OFFSET
0,2
COMMENTS
Row sums are 1-2n(n-1)=1-b(n). Inverse of A119828.
FORMULA
Column k has g.f. x^k(1-b(k+1)x) where b(n)=2n(2n-1).
EXAMPLE
Triangle begins
1,
-2, 1,
0, -12, 1,
0, 0, -30, 1,
0, 0, 0, -56, 1,
0, 0, 0, 0, -90, 1,
0, 0, 0, 0, 0, -132, 1,
0, 0, 0, 0, 0, 0, -182, 1,
0, 0, 0, 0, 0, 0, 0, -240, 1,
0, 0, 0, 0, 0, 0, 0, 0, -306, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, -380, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -462, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -552, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -650, 1
CROSSREFS
Sequence in context: A268434 A010107 A324429 * A268435 A039910 A352399
KEYWORD
easy,sign,tabl
AUTHOR
Paul Barry, May 25 2006
STATUS
approved