A145076 Coefficient of x^(6^n) in Q(x)^(n+1), where Q(x) = Sum_{k>=0} x^(6^k)*(1 - x^(5*6^k))/(1 - x^(6^k)).

1, 5, 25, 270, 3430, 52996, 968905, 20342540, 480982030, 12646108250, 365943140101, 11555148366323, 395323293564108

Offset

0,2

Links

Table of n, a(n) for n=0..12.

Maple

Q:=proc(x, n) options operator, arrow: sum(x^(6^k)+x^(2*6^k)+x^(3*6^k)+x^(4*6^k)+x^(5*6^k), k=0..n) end proc: seq(coeff(Q(x, n)^(n+1), x, 6^n), n=0..6); # Emeric Deutsch, Oct 20 2008

Prog

(PARI) {a(n, q=6)=local(Q=sum(j=0, n, (x^(q^j)-x^(q*q^j))/(1-x^(q^j)+O(x^(q^n+1))))); polcoeff(Q^(n+1), q^n)}

Crossrefs

Cf. A007178, A145073, A145074, A145075.

Sequence in context: A143600 A209529 A184958 * A185063 A165656 A370336

Adjacent sequences: A145073 A145074 A145075 * A145077 A145078 A145079

Keyword

more,nonn

Author

Paul D. Hanna, Oct 09 2008

Extensions

a(6) from Emeric Deutsch, Oct 20 2008

a(7)-a(12) from Max Alekseyev, Dec 19 2011

Status

approved