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A302697 Odd numbers whose prime indices are relatively prime. Heinz numbers of integer partitions with no 1's and with relatively prime parts. 20
15, 33, 35, 45, 51, 55, 69, 75, 77, 85, 93, 95, 99, 105, 119, 123, 135, 141, 143, 145, 153, 155, 161, 165, 175, 177, 187, 195, 201, 205, 207, 209, 215, 217, 219, 221, 225, 231, 245, 249, 253, 255, 265, 275, 279, 285, 287, 291, 295, 297, 309, 315, 323, 327, 329 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
A prime index of n is a number m such that prime(m) divides n.
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
LINKS
EXAMPLE
Sequence of integer partitions with no 1's and with relatively prime parts begins:
015: (3,2)
033: (5,2)
035: (4,3)
045: (3,2,2)
051: (7,2)
055: (5,3)
069: (9,2)
075: (3,3,2)
077: (5,4)
085: (7,3)
093: (11,2)
095: (8,3)
099: (5,2,2)
105: (4,3,2)
119: (7,4)
123: (13,2)
135: (3,2,2,2)
MATHEMATICA
primeMS[n_]:=If[n===1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
Select[Range[1, 200, 2], GCD@@primeMS[#]===1&]
CROSSREFS
Sequence in context: A177204 A342193 A343338 * A337987 A154369 A243592
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 11 2018
STATUS
approved

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Last modified May 11 19:59 EDT 2024. Contains 372413 sequences. (Running on oeis4.)