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%I #6 Jan 27 2020 18:49:34
%S 1,4,329,164410,217010257,592437912176,2900576017215049,
%T 23146596617368286854,281092269321320392419425,
%U 4933169326589172885999647452,120172004795712251502939402381001,3933950748992436265200224114943085394,168530450086835969601177601081838249796529
%N a(n) = 1/3!*(A000522(3*n) + 3*A000522(n) + 2).
%H Andrew Howroyd, <a href="/A086895/b086895.txt">Table of n, a(n) for n = 0..100</a>
%o (PARI) \\ here b(n) is A000522(n).
%o b(n)={sum(k=0, n, binomial(n, k)*k!)}
%o a(n)={(b(3*n) + 3*b(n) + 2) / 6} \\ _Andrew Howroyd_, Jan 27 2020
%Y Cf. A000522, A008290.
%K nonn
%O 0,2
%A _Vladeta Jovovic_, Aug 22 2003
%E Terms a(11) and beyond from _Andrew Howroyd_, Jan 27 2020
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