OFFSET
1,3
COMMENTS
The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).
LINKS
Wikipedia, Symmetric polynomial.
FORMULA
EXAMPLE
The sum of coefficients of 12h(32) = 2p(32) + 3p(221) + 2p(311) + 4p(2111) + p(11111) is a(15) = 12.
MATHEMATICA
f[p_, e_] := (PrimePi[p]!)^e; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 50] (* Amiram Eldar, Sep 10 2023 *)
CROSSREFS
KEYWORD
nonn,easy,mult
AUTHOR
Gus Wiseman, Nov 20 2018
STATUS
approved