login
Expansion of e.g.f. exp( Sum_{k>=0} x^(5*k+2) / (5*k+2)! ).
2

%I #41 Sep 24 2023 11:06:30

%S 1,0,1,0,3,0,15,1,105,36,945,990,10396,25740,136942,675675,2238405,

%T 18378361,50490765,523833819,1665638325,15790609395,71976549646,

%U 515107015830,3524757498023,19222751356875,181500385651325,888496839591076,9603885700913400

%N Expansion of e.g.f. exp( Sum_{k>=0} x^(5*k+2) / (5*k+2)! ).

%F a(0)=1; a(n) = Sum_{k=0..floor((n-2)/5)} binomial(n-1,5*k+1) * a(n-5*k-2).

%o (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(sum(k=0, N\5, x^(5*k+2)/(5*k+2)!))))

%Y Cf. A000296, A365338.

%K nonn

%O 0,5

%A _Seiichi Manyama_, Sep 22 2023