OFFSET
1,1
COMMENTS
Prime values of A000219.
LINKS
Eric Weisstein's World of Mathematics, Plane Partition
MAPLE
a:= proc(n) option remember; `if`(n=0, 1, add(
a(n-j)*numtheory[sigma][2](j), j=1..n)/n)
end:
select(isprime, [seq(a(n), n=0..800)])[]; # Alois P. Heinz, Dec 20 2023
MATHEMATICA
nmax = 750; Select[CoefficientList[Series[Product[1/(1 - x^k)^k, {k, 1, nmax}], {x, 0, nmax}], x], PrimeQ]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Dec 20 2023
STATUS
approved