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%I #10 May 24 2019 17:34:02
%S 1,0,15,2380,1056496,1006985994,1762986495425,5113595093793395,
%T 22839265373518360690,148735602883834110187329,
%U 1353820891564948063221216616,16652183007514287292261315076600,269267286009015985660399792630965620,5594310615550213586375706097295466365365
%N a(n) = (1/n!) * Sum_{i_1=1..4} Sum_{i_2=1..4} ... Sum_{i_n=1..4} (-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, 4*n, (-1)^i*i!*polcoef(sum(j=1, 4, x^j/j!)^n, i))/n!}
%Y Row n=4 of A308356.
%Y Cf. A144508.
%K nonn
%O 0,3
%A _Seiichi Manyama_, May 23 2019
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