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Expansion of e.g.f. exp(x/(1 - x^4)^(1/4)).
4

%I #15 Jun 10 2024 10:03:21

%S 1,1,1,1,1,31,181,631,1681,60481,687961,4379761,19982161,802740511,

%T 13848694861,131732390791,873339798241,38385869907841,894783905472241,

%U 11506538747852641,101612306808695521,4824806928717603871,142148609212891008421

%N Expansion of e.g.f. exp(x/(1 - x^4)^(1/4)).

%F a(n) = n! * Sum_{k=0..floor(n/4)} binomial(n/4-1,k)/(n-4*k)!.

%F a(n) == 1 mod 30.

%o (PARI) a(n) = n!*sum(k=0, n\4, binomial(n/4-1, k)/(n-4*k)!);

%Y Cf. A293507, A373520, A373521.

%Y Cf. A373524.

%K nonn

%O 0,6

%A _Seiichi Manyama_, Jun 08 2024