OFFSET
0,3
LINKS
Vaclav Kotesovec, Table of n, a(n) for n = 0..4500
FORMULA
From Vaclav Kotesovec, Aug 24 2018: (Start)
a(n) ~ c * A000032(n) * A000009(n) ~ c * phi^n * exp(Pi*sqrt(n/3)) / (4 * 3^(1/4) * n^(3/4)), where c = Product_{k>=1} ((1 + Lucas(k)/phi^k)/2) = 0.8503149035690839100210269103058319341315494385103929947491... and phi = A001622 = (1+sqrt(5))/2 is the golden ratio.
Equivalently, c = Product_{k>=1} (1 + (-1)^k/(2*phi^(2*k))),
c = 2/3 * QPochhammer[-1/2, -1/GoldenRatio^2]. (End)
MATHEMATICA
nmax = 40; CoefficientList[Series[Product[1+LucasL[k]*x^k, {k, 1, nmax}], {x, 0, nmax}], x]
nmax = 40; poly = ConstantArray[0, nmax + 1]; poly[[1]] = 1; poly[[2]] = 1; Do[Do[poly[[j + 1]] += LucasL[k]*poly[[j - k + 1]], {j, nmax, k, -1}]; , {k, 2, nmax}]; poly
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Aug 22 2018
STATUS
approved