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A324751
Number of strict integer partitions of n containing no prime indices of the parts.
23
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
OFFSET
0,5
COMMENTS
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.
EXAMPLE
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
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&Intersection[#, PrimePi/@First/@Join@@FactorInteger/@#]=={}&]], {n, 0, 30}]
CROSSREFS
The subset version is A324741, with maximal case A324743. The non-strict version is A324756. The Heinz number version is A324758. An infinite version is A304360.
Sequence in context: A376239 A332435 A361744 * A210595 A094435 A133341
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 16 2019
STATUS
approved