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A138211 G.f.: A(x) = 1 + x*(1 + x*(1 + x*(...(1 + x*(...)^(2n-1))...)^5)^3)^1.

%I A138211 #2 Mar 30 2012 18:37:09
%S A138211 1,1,1,3,18,166,2070,32505,614918,13600671,344202033,9806468970,
%T A138211 310553772735,10820519947581,411338412455910,16940944600551504,
%U A138211 751397442828052440,35707884976794347170,1810006747594245718317
%N A138211 G.f.: A(x) = 1 + x*(1 + x*(1 + x*(...(1 + x*(...)^(2n-1))...)^5)^3)^1.
%e A138211 G.f.: A(x)=1+x*B(x)^1, B(x)=1+x*C(x)^3, C(x)=1+x*D(x)^5, D(x)=1+x*E(x)^7, ...
%e A138211 where A(x),B(x),C(x),... are the g.f. of the sequences given below.
%e A138211 A=[1,1,1,3,18,166,2070,32505,614918,13600671,...];
%e A138211 B=[1,1,3,18,166,2070,32505,614918,13600671,344202033,...];
%e A138211 C=[1,1,5,45,570,9175,177836,4016810,103426120,2987875840,...];
%e A138211 D=[1,1,7,84,1358,26957,626871,16609768,492427321,16126773012,...];
%e A138211 E=[1,1,9,135,2658,62892,1712034,52281819,1762364970,64849739238,...];
%e A138211 F=[1,1,11,198,4598,126456,3950837,136929254,5186142291,212476739640,...];
%o A138211 (PARI) {a(n)=local(A=1+x+x*O(x^n)); for(j=0, n-1, A=1+x*A^(2*(n-j)-1)); polcoeff(A, n)}
%Y A138211 Cf. A095793, A138212, A138213, A138214, A138215, A138216.
%K A138211 nonn
%O A138211 0,4
%A A138211 _Paul D. Hanna_, Mar 06 2008