A367751 - OEIS

%I #10 Nov 29 2023 11:44:37

%S 1,1,3,13,73,501,4051,37633,394353,4596553,58941091,844031541,

%T 12949163833,213873687613,3782022682803,71267635330921,

%U 1439160383457121,30612704101371153,686728250047551043,16198763975779425373,400727742254252310441

%N E.g.f. satisfies A(x) = exp(x * (1 + x + x^2 + x^3 + x^4) * A(x^5)).

%F a(0) = 1; a(n) = (n-1)! * Sum_{k=0..n-1} (k+1) * a(floor(k/5)) * a(n-1-k) / (floor(k/5)! * (n-1-k)!).

%o (PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=(i-1)!*sum(j=0, i-1, (j+1)*v[j\5+1]*v[i-j]/((j\5)!*(i-1-j)!))); v;

%Y Cf. A367747, A367748, A367749.

%Y Cf. A367654.

%K nonn

%O 0,3

%A _Seiichi Manyama_, Nov 29 2023