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A138215 G.f.: A(x) = 1 + x*(1 + x*(1 + x*(...(1 + x*(...)^(5n))...)^15)^10)^5.

%I A138215 #2 Mar 30 2012 18:37:09
%S A138215 1,1,5,60,1185,32805,1169626,51021010,2631549790,156635460260,
%T A138215 10566145206715,796523479440060,66355853815084855,6053343246845576335,
%U A138215 600137100011260447750,64247982820612486908840
%N A138215 G.f.: A(x) = 1 + x*(1 + x*(1 + x*(...(1 + x*(...)^(5n))...)^15)^10)^5.
%e A138215 G.f.: A(x)=1+x*B(x)^5, B(x)=1+x*C(x)^10, C(x)=1+x*D(x)^15, D(x)=1+x*E(x)^20,...
%e A138215 where A(x),B(x),C(x),... are the g.f. of the sequences given below.
%e A138215 A=[1,1,5,60,1185,32805,1169626,51021010,2631549790,...];
%e A138215 B=[1,1,10,195,5520,202235,9038502,475490115,28745939090,...];
%e A138215 C=[1,1,15,405,15005,690165,37491378,2335884815,163755375450,...];
%e A138215 D=[1,1,20,690,31640,1756595,112818004,8165592610,654987108920,...];
%e A138215 E=[1,1,25,1050,57425,3739650,277763130,22962379750,2080527807050,...];
%e A138215 F=[1,1,30,1485,94360,7055580,595576506,55444469360,5610038179890,...]; ...
%o A138215 (PARI) {a(n)=local(A=1+x+x*O(x^n)); for(j=0, n-1, A=1+x*A^(5*(n-j))); polcoeff(A, n)}
%Y A138215 Cf. A095793, A138211, A138212, A138213, A138214, A138216.
%K A138215 nonn
%O A138215 0,3
%A A138215 _Paul D. Hanna_, Mar 06 2008