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 A104031 Column 1 of triangle A104030, which is the matrix inverse of the triangle of pairwise sums of trinomial coefficients. 1
 1, -5, 32, -299, 4015, -74080, 1801537, -55855829, 2150565968, -100668835739, 5630336915071, -370807060847872, 28403381397111649, -2503741873703550533, 251652633457563092096, -28608467296650576313259, 3652291148549164761101551, -520296573821474451201241696 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Column 0 of triangle A104030 forms signed Hammersley's polynomial p_n(1) (A006846), offset 1. LINKS 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)+ polcoeff((1+x+x^2)^(m-1)+O(x^(2*j)), 2*j-1))))^-1)[n+2, 2])} CROSSREFS Cf. A104030. Sequence in context: A331339 A307497 A023880 * A294957 A023882 A109780 Adjacent sequences:  A104028 A104029 A104030 * A104032 A104033 A104034 KEYWORD sign AUTHOR Paul D. Hanna, Feb 26 2005 STATUS approved

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Last modified January 18 13:30 EST 2020. Contains 331007 sequences. (Running on oeis4.)