login
A304711
Heinz numbers of integer partitions whose distinct parts are pairwise coprime.
32
2, 4, 6, 8, 10, 12, 14, 15, 16, 18, 20, 22, 24, 26, 28, 30, 32, 33, 34, 35, 36, 38, 40, 44, 45, 46, 48, 50, 51, 52, 54, 55, 56, 58, 60, 62, 64, 66, 68, 69, 70, 72, 74, 75, 76, 77, 80, 82, 85, 86, 88, 90, 92, 93, 94, 95, 96, 98, 99, 100, 102, 104, 106, 108, 110
OFFSET
1,1
COMMENTS
Two parts are coprime if they have no common divisor greater than 1. For partitions of length 1 note that (1) is coprime but (x) is not coprime for x > 1.
First differs from A289509 at a(24) = 44, A289509(24) = 42.
EXAMPLE
Sequence of all partitions whose distinct parts are pairwise coprime begins (1), (11), (21), (111), (31), (211), (41), (32), (1111), (221), (311), (51), (2111), (61), (411), (321), (11111), (52), (71), (43), (2211), (81), (3111).
MATHEMATICA
Select[Range[200], CoprimeQ@@PrimePi/@FactorInteger[#][[All, 1]]&]
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 17 2018
STATUS
approved