A324771 Numbers divisible by at least one of their prime indices > 1.
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
Offset: 1
Keywords
Examples
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}
Links
- Amiram Eldar, Table of n, a(n) for n = 1..10000
Crossrefs
Programs
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Mathematica
Select[Range[100],Or@@Cases[If[#==1,{},FactorInteger[#]],{p_?(#>2&),_}:>Divisible[#,PrimePi[p]]]&]
Comments