A353838 Numbers whose prime indices have all distinct run-sums.
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 61, 62, 64, 65, 66, 67, 68, 69, 70, 71
Offset: 1
Keywords
Examples
The prime indices of 180 are {1,1,2,2,3}, with run-sums (2,4,3), so 180 is in the sequence. The prime indices of 315 are {2,2,3,4}, with run-sums (4,3,4), so 315 is not in the sequence.
Crossrefs
Programs
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Mathematica
Select[Range[100],UnsameQ@@Cases[FactorInteger[#],{p_,k_}:>k*PrimePi[p]]&]
Comments