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(2) = 1 through a(10) = 9 integer partitions:
(2) (3) (4) (5) (6) (7) (8) (9) (A)
(22) (33) (43) (44) (54) (55)
(42) (52) (422) (63) (64)
(222) (2222) (72) (73)
(333) (82)
(522) (433)
(442)
(4222)
(22222)
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], !MemberQ[#, 1]&&Intersection[#, PrimePi/@First/@Join@@FactorInteger/@#]=={}&]], {n, 0, 30}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 17 2019
STATUS
approved