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A308390 a(n) = (1/n!) * Sum_{i_1=1..5} Sum_{i_2=1..5} ... Sum_{i_n=1..5} (-1)^(i_1 + i_2 + ... + i_n) * multinomial(i_1 + i_2 + ... + i_n; i_1, i_2, ..., i_n). 1

%I

%S 1,-1,56,-52556,197741887,-2063348839223,48406314676155689,

%T -2224972937386763396470,181775891472021264149048031,

%U -24546223741277444828277125708238,5178698199109137849496232609026642706,-1632057854975794517762778147823325297971400

%N a(n) = (1/n!) * Sum_{i_1=1..5} Sum_{i_2=1..5} ... Sum_{i_n=1..5} (-1)^(i_1 + i_2 + ... + i_n) * multinomial(i_1 + i_2 + ... + i_n; i_1, i_2, ..., i_n).

%o (PARI) {a(n) = sum(i=n, 5*n, (-1)^i*i!*polcoef(sum(j=1, 5, x^j/j!)^n, i))/n!}

%Y Row n=5 of A308356.

%Y Cf. A144509.

%K sign

%O 0,3

%A _Seiichi Manyama_, May 23 2019

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Last modified October 28 03:58 EDT 2021. Contains 348313 sequences. (Running on oeis4.)