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A324754 Number of integer partitions of n containing no part > 1 whose prime indices all belong to the partition. 8
1, 1, 2, 2, 4, 3, 7, 8, 11, 12, 19, 19, 30, 34, 46, 50, 71, 76, 104, 119, 151, 171, 225, 247, 315, 360, 446, 504, 629, 703, 867, 986, 1192, 1346, 1636, 1837, 2204, 2500, 2965, 3348, 3980, 4475, 5276, 5963, 6973, 7852, 9194, 10335, 12009, 13536, 15650, 17589 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

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.

For example, (6,2) is such a partition because the prime indices of 6 are {1,2}, which do not all belong to the partition. On the other hand, (5,3) is not such a partition because the prime indices of 5 are {3}, and 3 belongs to the partition.

LINKS

Table of n, a(n) for n=0..51.

EXAMPLE

The a(1) = 1 through a(8) = 11  integer partitions:

  (1)  (2)   (3)    (4)     (5)      (6)       (7)        (8)

       (11)  (111)  (22)    (311)    (33)      (43)       (44)

                    (31)    (11111)  (42)      (52)       (62)

                    (1111)           (51)      (61)       (71)

                                     (222)     (331)      (422)

                                     (3111)    (511)      (611)

                                     (111111)  (31111)    (2222)

                                               (1111111)  (3311)

                                                          (5111)

                                                          (311111)

                                                          (11111111)

MATHEMATICA

Table[Length[Select[IntegerPartitions[n], !MemberQ[#, k_/; SubsetQ[#, PrimePi/@First/@FactorInteger[k]]]&]], {n, 0, 30}]

CROSSREFS

The subset version is A324738, with maximal case A324744. The strict case is A324749. The Heinz number version is A324759. An infinite version is A324694.

Cf. A000837, A001462, A007097, A051424, A112798, A276625, A290822, A304360, A306844, A324695, A324750, A324755, A324760.

Sequence in context: A240010 A283502 A324756 * A174220 A048675 A162474

Adjacent sequences:  A324751 A324752 A324753 * A324755 A324756 A324757

KEYWORD

nonn

AUTHOR

Gus Wiseman, Mar 16 2019

STATUS

approved

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Last modified June 26 20:30 EDT 2019. Contains 324380 sequences. (Running on oeis4.)