A324748 Number of strict integer partitions of n containing all prime indices of the parts.
1, 1, 0, 1, 0, 1, 1, 1, 0, 2, 1, 2, 3, 2, 2, 4, 3, 4, 3, 5, 6, 9, 8, 7, 8, 11, 12, 13, 15, 17, 22, 22, 20, 28, 31, 32, 36, 41, 43, 53, 53, 59, 70, 76, 77, 89, 99, 108, 124, 135, 139, 160, 172, 188, 209, 229, 243, 274, 298, 315, 353, 391, 417, 457, 496, 538, 588
Offset: 0
Keywords
Examples
The first 15 terms count the following integer partitions. 1: (1) 3: (2,1) 5: (4,1) 6: (3,2,1) 7: (4,2,1) 9: (8,1) 9: (6,2,1) 10: (4,3,2,1) 11: (8,2,1) 11: (5,3,2,1) 12: (9,2,1) 12: (7,4,1) 12: (6,3,2,1) 13: (8,4,1) 13: (6,4,2,1) 14: (8,3,2,1) 14: (7,4,2,1) 15: (12,2,1) 15: (9,3,2,1) 15: (8,4,2,1) 15: (5,4,3,2,1) An example for n = 6 is (20,18,11,5,3,2,1), with prime indices: 20: {1,1,3} 18: {1,2,2} 11: {5} 5: {3} 3: {2} 2: {1} 1: {} All of these prime indices {1,2,3,5} belong to the partition, as required.
Crossrefs
Programs
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Mathematica
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&SubsetQ[#,PrimePi/@First/@Join@@FactorInteger/@DeleteCases[#,1]]&]],{n,0,30}]
Comments