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A324771 Numbers divisible by at least one of their prime indices > 1. 6
6, 12, 15, 18, 24, 28, 30, 36, 42, 45, 48, 54, 55, 56, 60, 66, 72, 75, 78, 84, 90, 96, 102, 105, 108, 110, 112, 114, 119, 120, 126, 132, 135, 138, 140, 144, 150, 152, 156, 162, 165, 168, 174, 180, 186, 192, 195, 196, 198, 204, 207, 210, 216, 220, 222, 224, 225 (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.
LINKS
EXAMPLE
The sequence of terms together with their prime indices begins:
6: {1,2}
12: {1,1,2}
15: {2,3}
18: {1,2,2}
24: {1,1,1,2}
28: {1,1,4}
30: {1,2,3}
36: {1,1,2,2}
42: {1,2,4}
45: {2,2,3}
48: {1,1,1,1,2}
54: {1,2,2,2}
55: {3,5}
56: {1,1,1,4}
60: {1,1,2,3}
66: {1,2,5}
72: {1,1,1,2,2}
75: {2,3,3}
78: {1,2,6}
84: {1,1,2,4}
MATHEMATICA
Select[Range[100], Or@@Cases[If[#==1, {}, FactorInteger[#]], {p_?(#>2&), _}:>Divisible[#, PrimePi[p]]]&]
CROSSREFS
Complement of A324849.
Sequence in context: A315615 A315616 A091011 * A104210 A356736 A066312
KEYWORD
nonn
AUTHOR
Gus Wiseman, Mar 18 2019
STATUS
approved

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Last modified March 29 05:48 EDT 2024. Contains 371265 sequences. (Running on oeis4.)