OFFSET
0,2
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..715
EXAMPLE
G.f.: A(x) = 1 + 2*x - 22*x^2 + 364*x^3 - 6490*x^4 + 124476*x^5 - 2501116*x^6 +...
where
A(x)^12 = 1 + 3*8*x + 5*8^2*x^3 + 7*8^3*x^6 + 9*8^4*x^10 + 11*8^5*x^15 + 13*8^6*x^21 + 15*8^7*x^28 + 17*8^8*x^36 + 19*8^9*x^45 + 21*8^10*x^55 +...
MAPLE
seq(coeff(series( ( add((2*n+1)*8^n*x^(n*(n+1)/2), n=0..40) )^(1/12), x, n+1), x, n), n = 0..30); # G. C. Greubel, Nov 05 2019
MATHEMATICA
CoefficientList[Series[(Sum[(2n+1)*8^n*x^(n(n+1)/2), {n, 0, 40}])^(1/12), {x, 0, 30}], x] (* G. C. Greubel, Nov 05 2019 *)
PROG
(PARI) {a(n)=polcoeff(sum(k=0, sqrtint(2*n+1), (2*k+1)*8^k*x^(k*(k+1)/2)+x*O(x^n))^(1/12), n)}
(Sage) [( (sum((2*n+1)*8^n*x^(n*(n+1)/2) for n in (0..40)) )^(1/12) ).series(x, n+1).list()[n] for n in (0..30)] # G. C. Greubel, Nov 05 2019
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, Aug 25 2005
STATUS
approved