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Main diagonal of A292133.
4

%I #20 Aug 21 2018 04:49:46

%S 1,-1,2,-21,220,-2705,40926,-733537,15124216,-352606050,9174382490,

%T -263533561852,8283376452948,-282795708021411,10420847619031710,

%U -412243715452039440,17425722339237083120,-783844576340696848341,37384875796116662077194

%N Main diagonal of A292133.

%H Seiichi Manyama, <a href="/A292134/b292134.txt">Table of n, a(n) for n = 0..386</a>

%F a(n) = [x^n] Product_{k>=1} 1/(1 + n*x^k).

%F a(n) ~ (-1)^n * n^n * (1 - 1/n + 2/n^2 - 3/n^3 + 5/n^4 - 7/n^5 + 11/n^6 - 15/n^7 + 22/n^8 - 30/n^9 + 42/n^10 - ...), for coefficients, see A000041. - _Vaclav Kotesovec_, Aug 21 2018

%o (PARI) {a(n) = polcoeff(1/prod(k=1, n, 1+n*x^k+x*O(x^n)), n)}

%Y Cf. A124577, A291698.

%K sign

%O 0,3

%A _Seiichi Manyama_, Sep 09 2017