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 A255348 a(1)=1, a(2) = 2; for n > 2, a(n) is the smallest number not already used such that the set of prime divisors of one of the numbers {a(n-1), a(n)} is a subset of the set of prime divisors of the other. 2
 1, 2, 4, 6, 3, 9, 12, 8, 10, 5, 15, 25, 20, 16, 14, 7, 21, 27, 18, 24, 30, 32, 22, 11, 33, 66, 36, 42, 28, 49, 35, 70, 40, 50, 60, 45, 75, 81, 39, 13, 26, 52, 64, 34, 17, 51, 102, 48, 54, 72, 78, 96, 84, 56, 98, 112, 126, 63, 105, 125, 55, 110, 44, 88, 121, 77 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The sequence is an analog of EKG-sequence A064413 with more hard condition on neighbor terms. However, we conjecture that, as A064413, it is a permutation of the positive integers. By the definition, every two neighbor terms are strictly connected numbers defined in comment in A257112. LINKS Peter J. C. Moses, Table of n, a(n) for n = 1..5000 CROSSREFS Cf. A064413, A257112. Sequence in context: A338338 A096665 A064413 * A336946 A122280 A291577 Adjacent sequences:  A255345 A255346 A255347 * A255349 A255350 A255351 KEYWORD nonn AUTHOR Vladimir Shevelev, May 05 2015 EXTENSIONS More terms from Peter J. C. Moses, May 05 2015 STATUS approved

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Last modified December 5 09:47 EST 2020. Contains 338945 sequences. (Running on oeis4.)