%I #24 Sep 24 2023 09:15:58
%S 1,1,1,1,1,1,121,841,3361,10081,25201,3684241,50309281,369738721,
%T 1926648361,7980936601,1335634023361,27705746752321,302258931418081,
%U 2283161710263841,13419441405835201,2498339829188508481,70152448708746111961,1025314852704395518441
%N Expansion of e.g.f. exp( Sum_{k>=0} x^(5*k+1) / (5*k+1) ).
%F a(0) = 1; a(n) = (n-1)! * Sum_{k=0..floor((n-1)/5)} a(n-5*k-1)/(n-5*k-1)!.
%F a(0) = a(1) = ... = a(4) = 1; a(n) = a(n-1) + 120 * binomial(n-1,5) * a(n-5).
%o (PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(sum(k=0, N\5, x^(5*k+1)/(5*k+1)))))
%Y Cf. A000246, A193437, A193438.
%Y Cf. A333882, A365977.
%K nonn
%O 0,7
%A _Seiichi Manyama_, Sep 23 2023
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