A227294 G.f.: ( Sum_{n>=0} 8^n*x^(n^2) )^(1/4).

1, 2, -6, 28, -138, 828, -5180, 33528, -223002, 1512812, -10423796, 72743688, -513005252, 3649850584, -26162987064, 188758837488, -1369529290618, 9985780112460, -73129564342212, 537647977891688, -3966638722824108, 29357430489994120, -217899481094085320, 1621534636345991568, -12095712639252241956

Offset

0,2

Links

Table of n, a(n) for n=0..24.

Example

G.f.: A(x) = 1 + 2*x - 6*x^2 + 28*x^3 - 138*x^4 + 828*x^5 - 5180*x^6 + 33528*x^7 - 223002*x^8 + 1512812*x^9 - 10423796*x^10 +...
where
A(x)^4 = 1 + 8*x + 8^2*x^4 + 8^3*x^9 + 8^4*x^16 + 8^5*x^25 + 8^6*x^36 +...

Prog

(PARI) {a(n)=polcoeff((sum(k=0, n, 8^k*x^(k^2))+x*O(x^n))^(1/4), n)}
for(n=0, 36, print1(a(n), ", "))

Crossrefs

Cf. A227293, A227295.

Sequence in context: A226497 A307523 A065577 * A302336 A225877 A350524

Adjacent sequences: A227291 A227292 A227293 * A227295 A227296 A227297

Keyword

sign

Author

Paul D. Hanna, Jul 05 2013

Status

approved