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%I #12 Apr 05 2026 13:16:59
%S -1,0,0,0,1,4,19,111,760,5976,53062,524919,5723493,68181821,880916799,
%T 12267980944,183181681783,2919228642272,49452334100912,
%U 887356817041401,16812532278748455,335401627901612613,7027324571812426900,154279299692901768147,3541671282222287112486
%N G.f. A(x) satisfies A(x) = -1 / (1 + x - x^2 + x^3 - x * d/dx log(1 - x*A(x))).
%H Seiichi Manyama, <a href="/A394879/b394879.txt">Table of n, a(n) for n = 0..451</a>
%F a(0) = -1, a(1) = a(2) = a(3) = 0; a(n) = (n-1)/2 * a(n-1) - a(n-4) - ((n-1)/2 * b(n-1) - b(n-2) + b(n-3) - b(n-4)), where b(n) = Sum_{k=1..n} a(k)*a(n-k).
%Y Cf. A075834, A394877, A394878, A394880, A394881.
%K sign
%O 0,6
%A _Seiichi Manyama_, Apr 05 2026