OFFSET
0,3
COMMENTS
See A338559 for details.
LINKS
Amiram Eldar, Table of n, a(n) for n = 0..214
MATHEMATICA
psi[1] = 1; psi[n_] := n*Times @@ (1 + 1/Transpose[FactorInteger[n]][[1]]); delta[ps_] := 1/psi[(Times @@ ps)*(Times @@ Union[ps])]; f[n_] := Total[delta /@ IntegerPartitions[n, Floor[n/2], Select[Range[n], PrimeQ]]]; Denominator @ Array[f, 30, 0]
CROSSREFS
KEYWORD
nonn,frac
AUTHOR
Amiram Eldar, Nov 02 2020
STATUS
approved