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
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 16 2019
STATUS
approved