A376163 - OEIS

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A376163

Positions of adjacent non-prime-powers (inclusive, so 1 is a prime-power) differing by 1.

4, 7, 8, 14, 15, 16, 18, 19, 22, 23, 26, 27, 29, 30, 31, 32, 35, 37, 39, 40, 43, 44, 45, 46, 50, 51, 52, 53, 55, 56, 57, 58, 59, 60, 62, 63, 66, 67, 70, 71, 73, 74, 75, 76, 77, 78, 80, 81, 84, 86, 87, 88, 89, 92, 93, 94, 95, 96, 97, 98, 99, 102, 103, 104, 105

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..65.

EXAMPLE

The non-prime-powers (inclusive) are 6, 10, 12, 14, 15, 18, 20, 21, 22, 24, ... which increase by 1 after positions 4, 7, 8, ...

MATHEMATICA

ce=Select[Range[2, 100], !PrimePowerQ[#]&];

Select[Range[Length[ce]-1], ce[[#+1]]==ce[[#]]+1&]

CROSSREFS

For prime-powers inclusive (A000961) we have A375734, differences A373671.