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 A318400 Numbers whose prime indices are all powers of 2 (including 1). 10
 1, 2, 3, 4, 6, 7, 8, 9, 12, 14, 16, 18, 19, 21, 24, 27, 28, 32, 36, 38, 42, 48, 49, 53, 54, 56, 57, 63, 64, 72, 76, 81, 84, 96, 98, 106, 108, 112, 114, 126, 128, 131, 133, 144, 147, 152, 159, 162, 168, 171, 189, 192, 196, 212, 216, 224, 228, 243, 252, 256, 262 (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. The multiset of prime indices of n is row n of A112798. LINKS EXAMPLE The sequence of all integer partitions whose parts are all powers of 2 (including 1) begins: (), (1), (2), (11), (21), (4), (111), (22), (211), (41), (1111), (221), (8), (42), (2111), (222), (411), (11111), (2211), (81), (421), (21111), (44). MATHEMATICA primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]]; pow2Q[n_]:=Or[n==1, MatchQ[FactorInteger[n], {{2, _}}]]; Select[Range[100], And@@pow2Q/@primeMS[#]&] CROSSREFS Cf. A003963, A018819, A033844, A056239, A106349, A112798, A302242, A302491, A322551. Sequence in context: A010408 A010455 A269804 * A219174 A108319 A177500 Adjacent sequences:  A318397 A318398 A318399 * A318401 A318402 A318403 KEYWORD nonn AUTHOR Gus Wiseman, Dec 16 2018 STATUS approved

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Last modified June 22 16:15 EDT 2021. Contains 345386 sequences. (Running on oeis4.)