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A362011
Numbers k such that 1 < gcd(k, 70) < k and A007947(k) does not divide 70.
1
6, 12, 15, 18, 21, 22, 24, 26, 30, 34, 36, 38, 42, 44, 45, 46, 48, 52, 54, 55, 58, 60, 62, 63, 65, 66, 68, 72, 74, 75, 76, 77, 78, 82, 84, 85, 86, 88, 90, 91, 92, 94, 95, 96, 102, 104, 105, 106, 108, 110, 114, 115, 116, 118, 119, 120, 122, 124, 126, 130, 132, 133, 134, 135, 136, 138, 142, 144, 145, 146
OFFSET
1,1
COMMENTS
The asymptotic density of this sequence is 23/35. - Amiram Eldar, Dec 02 2023
LINKS
Michael De Vlieger, Diagram showing numbers k in this sequence instead as k mod 70 arranged in rows, labeled and in large black circles, else gray dots if coprime to 70, purple if k = 1, red if k | 70, and gold if rad(k) | 70.
FORMULA
This sequence is { N \ { A108513 U A235583 } }.
MATHEMATICA
With[{n = 70}, Select[Range[200], And[! CoprimeQ[#, n], ! Divisible[n, Times @@ FactorInteger[#][[All, 1]]]] & ] ]
CROSSREFS
KEYWORD
nonn
AUTHOR
Michael De Vlieger, Apr 04 2023
STATUS
approved