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A078635
Number of partitions of n into perfect powers.
7
1, 1, 1, 1, 2, 2, 2, 2, 4, 5, 5, 5, 7, 8, 8, 8, 12, 14, 15, 15, 19, 21, 22, 22, 28, 33, 35, 37, 43, 48, 50, 52, 62, 70, 75, 79, 92, 100, 105, 109, 126, 140, 148, 157, 177, 194, 202, 211, 237, 261, 276, 290, 324, 351, 370, 384, 424, 462, 489, 514, 562, 609, 640, 670, 728
OFFSET
0,5
LINKS
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
Cf. A001597.
Cf. A131799.
Sequence in context: A230447 A029078 A131799 * A286305 A046768 A363405
KEYWORD
nonn
AUTHOR
Henry Bottomley, Dec 12 2002
STATUS
approved