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 A324926 Numbers not divisible by any prime indices of their prime indices. 7
 1, 2, 4, 5, 8, 11, 16, 17, 22, 23, 25, 31, 32, 34, 41, 44, 47, 55, 59, 62, 64, 67, 73, 82, 83, 85, 88, 97, 103, 109, 115, 118, 121, 124, 125, 127, 128, 134, 137, 149, 157, 164, 166, 167, 176, 179, 187, 191, 194, 197, 205, 211, 218, 227, 233, 235, 236, 241, 242 (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. For example, the prime indices of 55 are {3,5} with prime indices {{2},{3}}. Since 55 is not divisible by 2 or 3, it belongs to the sequence. LINKS EXAMPLE The sequence of multisets of multisets whose MM-numbers (see A302242) belong to the sequence begins:    1: {}    2: {{}}    4: {{},{}}    5: {{2}}    8: {{},{},{}}   11: {{3}}   16: {{},{},{},{}}   17: {{4}}   22: {{},{3}}   23: {{2,2}}   25: {{2},{2}}   31: {{5}}   32: {{},{},{},{},{}}   34: {{},{4}}   41: {{6}}   44: {{},{},{3}}   47: {{2,3}}   55: {{2},{3}}   59: {{7}}   62: {{},{5}}   64: {{},{},{},{},{},{}} MATHEMATICA primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]]; Select[Range[100], And@@Table[!Divisible[#, i], {i, Union@@primeMS/@primeMS[#]}]&] CROSSREFS Cf. A001222, A003963, A112798, A120383, A302242, A304360, A324846, A324847, A324848, A324849, A324850, A324927, A324928, A324930. Sequence in context: A222044 A288937 A327063 * A175106 A216566 A205728 Adjacent sequences:  A324923 A324924 A324925 * A324927 A324928 A324929 KEYWORD nonn AUTHOR Gus Wiseman, Mar 21 2019 STATUS approved

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Last modified April 6 07:02 EDT 2020. Contains 333267 sequences. (Running on oeis4.)