OFFSET
0,57
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
Eric Weisstein's World of Mathematics, Cuban Prime
Eric Weisstein's World of Mathematics, Hex Number
FORMULA
G.f.: Product_{k>=1} 1/(1 - x^A002407(k)).
EXAMPLE
a(56) = 2 because we have [37, 19] and [7, 7, 7, 7, 7, 7, 7, 7].
MATHEMATICA
nmax = 100; CoefficientList[Series[Product[1/(1 - x^k), {k, Select[(Range[nmax] + 1)^3 - Range[nmax]^3, PrimeQ]}], {x, 0, nmax}], x]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, May 16 2017
STATUS
approved