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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 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Row sums are 1-2n(n-1)=1-b(n). Inverse of A119828.

LINKS

Table of n, a(n) for n=0..96.

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 A129467

Adjacent sequences:  A119827 A119828 A119829 * A119831 A119832 A119833

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry, May 25 2006

STATUS

approved

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Last modified September 17 06:52 EDT 2019. Contains 327119 sequences. (Running on oeis4.)