A138216 G.f.: A(x) = 1 + x*(1 + x*(1 + x*(...(1 + x*(...)^(6n))...)^18)^12)^6.

1, 1, 6, 87, 2072, 69051, 2960496, 155190175, 9614870340, 687262107456, 55663739264928, 5037617218937667, 503778146624222544, 55164755650126969274, 6564517420892162939514, 843494176565238712267131

Offset

0,3

Links

Table of n, a(n) for n=0..15.

Example

G.f.: A(x)=1+x*B(x)^6, B(x)=1+x*C(x)^12, C(x)=1+x*D(x)^18, D(x)=1+x*E(x)^24,...
where A(x),B(x),C(x),... are the g.f. of the sequences given below.
A=[1,1,6,87,2072,69051,2960496,155190175,9614870340,...];
B=[1,1,12,282,9616,424035,22794444,1441538178,104721633324,...];
C=[1,1,18,585,26088,1443708,94316940,7064386296,595172880432,...];
D=[1,1,24,996,54944,3668826,283322664,24650121400,2376215009736,...];
E=[1,1,30,1515,99640,7802145,696663576,69221991825,7536986249580,...];
F=[1,1,36,2142,163632,14708421,1492326612,166960071642,...]; ...

Prog

(PARI) {a(n)=local(A=1+x+x*O(x^n)); for(j=0, n-1, A=1+x*A^(6*(n-j))); polcoeff(A, n)}

Crossrefs

Cf. A095793, A138211, A138212, A138213, A138214, A138215.

Sequence in context: A123544 A239749 A277337 * A294491 A239750 A245984

Adjacent sequences: A138213 A138214 A138215 * A138217 A138218 A138219

Keyword

nonn

Author

Paul D. Hanna, Mar 06 2008

Status

approved