OFFSET
0,5
LINKS
Michael De Vlieger, Table of n, a(n) for n = 0..10000
FORMULA
G.f.: Product_{k=i^j, i>=1, j>=2, excluding duplicates} 1/(1 - x^k). - Ilya Gutkovskiy, Mar 21 2017
EXAMPLE
a(10)=5 since 10 can be written as 9+1, 8+1+1, 4+4+1+1, 4+1+1+1+1+1+1, or 1+1+1+1+1+1+1+1+1+1.
MATHEMATICA
t = Union[Flatten[Table[n^k, {n, 1, 60}, {k, 2, 10}]]]; p[n_] := IntegerPartitions[n, All, t]; Table[p[n], {n, 0, 12}] (*shows partitions*)
a[n_] := Length@p@n; a /@ Range[0, 80]
(* Clark Kimberling, Mar 09 2014 *)
With[{nn = 64}, CoefficientList[Series[Product[1/(1 - x^k), {k, Select[Range[nn], # == 1 || GCD @@ FactorInteger[#][[All, -1]] > 1 &]}], {x, 0, nn}], x]] (* Michael De Vlieger, Sep 06 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Henry Bottomley, Dec 12 2002
STATUS
approved