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%I #10 Sep 20 2023 10:01:10
%S 1,7,74,931,12894,189798,2913980,46140347,748022678,12354604274,
%T 207148525484,3516699607022,60328735646620,1044182053141612,
%U 18212018061261600,319771572646888811,5647677332549552870,100266714048150595770,1788366334642393259292
%N Expansion of (1/x) * Series_Reversion( x*(1-x)^4/(1+x)^3 ).
%F a(n) = (1/(n+1)) * Sum_{k=0..n} binomial(4*n+k+3,k) * binomial(3*(n+1),n-k).
%o (PARI) a(n) = sum(k=0, n, binomial(4*n+k+3, k)*binomial(3*(n+1), n-k))/(n+1);
%Y Cf. A007297, A365842, A365843, A365845.
%K nonn
%O 0,2
%A _Seiichi Manyama_, Sep 20 2023