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 A324705 Lexicographically earliest sequence containing 1 and all composite numbers divisible by prime(m) for some m already in the sequence. 12
 1, 4, 6, 8, 10, 12, 14, 16, 18, 20, 21, 22, 24, 26, 28, 30, 32, 34, 35, 36, 38, 39, 40, 42, 44, 46, 48, 49, 50, 52, 54, 56, 57, 58, 60, 62, 63, 64, 65, 66, 68, 70, 72, 74, 76, 77, 78, 80, 82, 84, 86, 87, 88, 90, 91, 92, 94, 95, 96, 98, 100, 102, 104, 105, 106 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A self-describing sequence, similar to A304360. 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 Table of n, a(n) for n=1..65. EXAMPLE The sequence of terms together with their prime indices begins: 1: {} 4: {1,1} 6: {1,2} 8: {1,1,1} 10: {1,3} 12: {1,1,2} 14: {1,4} 16: {1,1,1,1} 18: {1,2,2} 20: {1,1,3} 21: {2,4} 22: {1,5} 24: {1,1,1,2} 26: {1,6} 28: {1,1,4} 30: {1,2,3} 32: {1,1,1,1,1} 34: {1,7} 35: {3,4} 36: {1,1,2,2} MATHEMATICA aQ[n_]:=Switch[n, 1, True, _?PrimeQ, False, _, !And@@Cases[FactorInteger[n], {p_, k_}:>!aQ[PrimePi[p]]]]; Select[Range[200], aQ] CROSSREFS Complement of A324697. Cf. A000002, A000720, A001222, A001462, A007097, A055396, A061395, A079000, A079254, A109298, A112798, A276625, A277098, A304360. Cf. A324694, A324695, A324696, A324698, A324699, A324700, A324701, A324702, A324703, A324704. Sequence in context: A185604 A054023 A330948 * A032583 A175074 A063127 Adjacent sequences: A324702 A324703 A324704 * A324706 A324707 A324708 KEYWORD nonn AUTHOR Gus Wiseman, Mar 11 2019 STATUS approved

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Last modified September 23 19:57 EDT 2023. Contains 365554 sequences. (Running on oeis4.)