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A322912
Number of integer partitions of n whose parts are all powers of the same squarefree number.
3
1, 1, 2, 3, 5, 6, 10, 11, 15, 17, 23, 24, 33, 34, 42, 46, 56, 57, 71, 72, 88, 93, 109, 110, 134, 136, 158, 163, 191, 192, 229, 230, 266, 273, 311, 315, 370, 371, 419, 428, 491, 492, 565, 566, 642, 654, 730, 731, 836, 838, 936
OFFSET
0,3
COMMENTS
First differs from A072720 at a(12) = 33, A072720(12) = 34.
EXAMPLE
The a(1) = 1 through a(8) = 15 integer partitions:
(1) (2) (3) (4) (5) (6) (7) (8)
(11) (21) (22) (41) (33) (61) (44)
(111) (31) (221) (42) (331) (71)
(211) (311) (51) (421) (422)
(1111) (2111) (222) (511) (611)
(11111) (411) (2221) (2222)
(2211) (4111) (3311)
(3111) (22111) (4211)
(21111) (31111) (5111)
(111111) (211111) (22211)
(1111111) (41111)
(221111)
(311111)
(2111111)
(11111111)
MATHEMATICA
radbase[n_]:=n^(1/GCD@@FactorInteger[n][[All, 2]]);
powsqfQ[n_]:=SameQ@@Last/@FactorInteger[n];
Table[Length[Select[IntegerPartitions[n], And[And@@powsqfQ/@#, SameQ@@radbase/@DeleteCases[#, 1]]&]], {n, 30}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Dec 30 2018
STATUS
approved