This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A371120 #9 Mar 11 2024 08:29:42
%S A371120 1,0,2,3,100,545,17946,203497,7194440,132963777,5172409630,
%T A371120 135827977241,5868623306844,200952952956769,9665278822378466,
%U A371120 407661518051710665,21789972653746494736,1088515671895571005313,64406426353877958253254
%N A371120 E.g.f. satisfies A(x) = 1 + x*A(x)^3*(exp(x*A(x)) - 1).
%F A371120 a(n) = n! * Sum_{k=0..floor(n/2)} (n+2*k)! * Stirling2(n-k,k)/( (n-k)! * (n+k+1)! ).
%o A371120 (PARI) a(n) = n!*sum(k=0, n\2, (n+2*k)!*stirling(n-k, k, 2)/((n-k)!*(n+k+1)!));
%Y A371120 Cf. A370988, A371115, A371119.
%Y A371120 Cf. A371122.
%K A371120 nonn
%O A371120 0,3
%A A371120 _Seiichi Manyama_, Mar 11 2024