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A324751
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Number of strict integer partitions of n containing no prime indices of the parts.
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23
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1, 1, 1, 1, 2, 1, 3, 3, 2, 4, 5, 5, 6, 8, 8, 12, 10, 14, 13, 18, 19, 26, 25, 30, 34, 39, 40, 51, 55, 60, 71, 77, 90, 97, 111, 123, 136, 153, 170, 179, 216, 230, 264, 282, 322, 345, 385, 423, 470, 513, 573, 629, 686, 755, 834, 910, 1005, 1095, 1194, 1303, 1433
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OFFSET
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0,5
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COMMENTS
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A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
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LINKS
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EXAMPLE
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The a(1) = 1 through a(13) = 8 strict integer partitions (A...D = 10...13):
1 2 3 4 5 6 7 8 9 A B C D
31 42 43 71 54 64 65 75 76
51 52 63 73 83 84 85
72 82 542 93 94
91 731 A2 B2
B1 643
751
931
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MATHEMATICA
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Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&Intersection[#, PrimePi/@First/@Join@@FactorInteger/@#]=={}&]], {n, 0, 30}]
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CROSSREFS
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Cf. A000720, A001462, A007097, A074971, A078374, A112798, A276625, A290822, A305713, A306844, A324764.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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