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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 Cf. A000961, A001222, A003963, A005117, A007716, A056239, A275024, A047966, A281113, A296134, A301766, A302242, A302243. Sequence in context: A130689 A024560 A000039 * A053436 A057546 A138587 Adjacent sequences:  A302597 A302598 A302599 * A302601 A302602 A302603 KEYWORD nonn AUTHOR Gus Wiseman, Apr 10 2018 STATUS approved

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Last modified September 28 13:24 EDT 2020. Contains 337393 sequences. (Running on oeis4.)