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A104028 Column 1 of triangle A104027, which is the matrix inverse of the triangle A056241 of even-indexed trinomial coefficients. 1
1, -3, 12, -73, 675, -9048, 166901, -4058703, 125837748, -4845013765, 226796981895, -12684595018992, 835391818484873, -63990023222817531, 5640684058036591260, -566948619030797914657, 64452061572236327204235, -8228252550026752605862344 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Column 0 of triangle A104027 forms signed Hammersley's polynomial p_n(1) (A006846).

LINKS

Table of n, a(n) for n=0..17.

PROG

(PARI) {a(n)=if(n<0, 0, ((matrix(n+2, n+2, m, j, if(m>=j, polcoeff((1+x+x^2)^(m-1)+O(x^(2*j)), 2*j-2))))^-1)[n+2, 2])}

CROSSREFS

Cf. A104027, A006846.

Sequence in context: A247055 A163860 A246382 * A074510 A317184 A342599

Adjacent sequences:  A104025 A104026 A104027 * A104029 A104030 A104031

KEYWORD

sign

AUTHOR

Paul D. Hanna, Feb 26 2005

STATUS

approved

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Last modified July 30 23:12 EDT 2021. Contains 346365 sequences. (Running on oeis4.)