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 A285386 Lexicographically earliest sequence of distinct positive terms such that the product of two consecutive terms is divisible by p^4 for some prime p. 2
 1, 16, 2, 8, 4, 12, 20, 24, 6, 27, 3, 32, 5, 48, 7, 64, 9, 18, 36, 28, 40, 10, 56, 14, 72, 22, 80, 11, 81, 13, 96, 15, 54, 21, 108, 30, 88, 26, 104, 34, 112, 17, 128, 19, 144, 23, 160, 25, 50, 75, 100, 44, 52, 60, 68, 76, 84, 92, 116, 120, 38, 136, 42, 135, 33 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS This sequence is a permutation of the natural numbers. LINKS Rémy Sigrist, Table of n, a(n) for n = 1..10000 Rémy Sigrist, C++ program for A285386 Rémy Sigrist, Scatterplot of the first 100000 terms EXAMPLE The first terms, alongside the primes p such that p^4 divides a(n)*a(n+1), are: n       a(n)    p --      ----    - 1       1       2 2       16      2 3       2       2 4       8       2 5       4       2 6       12      2 7       20      2 8       24      2 9       6       3 10      27      3 11      3       2 12      32      2 13      5       2 14      48      2 15      7       2 16      64      2 17      9       3 18      18      3 19      36      2 20      28      2 ... 165     95      2 166     432     2, 3 167     87      3 ... CROSSREFS Cf. A285296. Sequence in context: A040253 A180730 A040254 * A100079 A144532 A270570 Adjacent sequences:  A285383 A285384 A285385 * A285387 A285388 A285389 KEYWORD nonn AUTHOR Rémy Sigrist, Apr 18 2017 STATUS approved

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Last modified June 22 09:57 EDT 2021. Contains 345375 sequences. (Running on oeis4.)