A323088 Number of strict integer partitions of n using numbers that are not perfect powers.
1, 0, 1, 1, 0, 2, 1, 2, 2, 2, 3, 3, 4, 5, 5, 7, 7, 9, 11, 11, 15, 16, 18, 22, 24, 27, 32, 34, 41, 45, 51, 59, 64, 75, 82, 94, 105, 116, 132, 146, 163, 183, 202, 225, 251, 277, 309, 341, 378, 417, 463, 510, 564, 622, 685, 754, 830, 914, 1001, 1103, 1207, 1325
Offset: 0
Keywords
Examples
A list of all strict integer partitions using numbers that are not perfect powers begins: 2: (2) 11: (6,3,2) 15: (13,2) 17: (12,5) 3: (3) 12: (12) 15: (12,3) 17: (12,3,2) 5: (5) 12: (10,2) 15: (10,5) 17: (11,6) 5: (3,2) 12: (7,5) 15: (10,3,2) 17: (10,7) 6: (6) 12: (7,3,2) 15: (7,6,2) 17: (10,5,2) 7: (7) 13: (13) 15: (7,5,3) 17: (7,5,3,2) 7: (5,2) 13: (11,2) 16: (14,2) 18: (18) 8: (6,2) 13: (10,3) 16: (13,3) 18: (15,3) 8: (5,3) 13: (7,6) 16: (11,5) 18: (13,5) 9: (7,2) 13: (6,5,2) 16: (11,3,2) 18: (13,3,2) 9: (6,3) 14: (14) 16: (10,6) 18: (12,6) 10: (10) 14: (12,2) 16: (7,6,3) 18: (11,7) 10: (7,3) 14: (11,3) 16: (6,5,3,2) 18: (11,5,2) 10: (5,3,2) 14: (7,5,2) 17: (17) 18: (10,6,2) 11: (11) 14: (6,5,3) 17: (15,2) 18: (10,5,3) 11: (6,5) 15: (15) 17: (14,3) 18: (7,6,5)
Crossrefs
Programs
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Mathematica
perpowQ[n_]:=GCD@@FactorInteger[n][[All,2]]>1; Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&FreeQ[#,1]&&And@@Not/@perpowQ/@#&]],{n,20}]
Formula
O.g.f.: Product_{n in A007916} (1 + x^n).