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A302600 1, 2, prime numbers of prime index, and prime numbers of prime index times 2. 0
1, 2, 3, 5, 6, 10, 11, 17, 22, 31, 34, 41, 59, 62, 67, 82, 83, 109, 118, 127, 134, 157, 166, 179, 191, 211, 218, 241, 254, 277, 283, 314, 331, 353, 358, 367, 382, 401, 422, 431, 461, 482, 509, 547, 554, 563, 566, 587, 599, 617, 662, 706, 709, 734, 739, 773 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
A prime index of n is a number m such that prime(m) divides n.
Also squarefree numbers whose prime indices other than 1 are equal prime numbers.
LINKS
EXAMPLE
Entry A302242 describes a correspondence between positive integers and multiset multisystems. In this case it gives the following sequence of set systems.
01: {}
02: {{}}
03: {{1}}
05: {{2}}
06: {{},{1}}
10: {{},{2}}
11: {{3}}
17: {{4}}
22: {{},{3}}
31: {{5}}
34: {{},{4}}
41: {{6}}
59: {{7}}
62: {{},{5}}
67: {{8}}
82: {{},{6}}
83: {{9}}
MATHEMATICA
Select[Range[1000], SquareFreeQ[#]&&SameQ@@DeleteCases[primeMS[#], 1]&&And@@PrimeQ/@DeleteCases[primeMS[#], 1]&]
CROSSREFS
Sequence in context: A130689 A024560 A000039 * A053436 A057546 A339514
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 10 2018
STATUS
approved

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Last modified March 19 03:33 EDT 2024. Contains 370952 sequences. (Running on oeis4.)