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%I #5 Dec 19 2024 10:10:22
%S 1,2,26,506,11650,294338,7889658,220337562,6341770050,186793134530,
%T 5603256962842,170587626013306,5257389708399426,163705194058656258,
%U 5142396822771086970,162763301041914082970,5185766155796261822338,166183971861135163491458
%N G.f. A(x) satisfies A(x) = 1 + x * A(x)^4 * (1 + A(x)^5).
%F a(n) = Sum_{k=0..n} binomial(n,k) * binomial(4*n+5*k+1,n)/(4*n+5*k+1).
%o (PARI) a(n) = sum(k=0, n, binomial(n, k)*binomial(4*n+5*k+1, n)/(4*n+5*k+1));
%Y Cf. A363380.
%K nonn,new
%O 0,2
%A _Seiichi Manyama_, Dec 18 2024