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 A308327 a(n) = (1/n!) * Sum_{i_1=1..n} Sum_{i_2=1..n} ... Sum_{i_n=1..n} (-1)^(i_1 + i_2 + ... + i_n) * multinomial(i_1 + i_2 + ... + i_n; i_1, i_2, ..., i_n). 2
 1, -1, 1, -120, 1056496, -2063348839223, 1457689055077930674637, -569779896381467292745562607320194, 174622933743914766946635359968704455433117668396, -56466564044341292662007179162722871704054012257606338926938133618 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 LINKS Seiichi Manyama, Table of n, a(n) for n = 0..27 EXAMPLE a(2) = (1/2) * (binomial(1+1,1) - binomial(1+2,2) - binomial(2+1,1) + binomial(2+2,2)) = 1. PROG (PARI) {a(n) = sum(i=n, n^2, (-1)^i*i!*polcoef(sum(j=1, n, x^j/j!)^n, i))/n!} CROSSREFS Main diagonal of A308356. Cf. A308296. Sequence in context: A166351 A147964 A172857 * A172897 A258925 A100734 Adjacent sequences:  A308324 A308325 A308326 * A308328 A308329 A308330 KEYWORD sign AUTHOR Seiichi Manyama, May 20 2019 STATUS approved

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Last modified August 12 04:28 EDT 2022. Contains 356067 sequences. (Running on oeis4.)