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 A285417 Lexicographically earliest sequence of distinct positive terms such that the product of two consecutive terms is divisible by p^5 for some prime p. 2
 1, 32, 2, 16, 4, 8, 12, 24, 20, 40, 28, 48, 6, 64, 3, 81, 9, 27, 18, 54, 36, 56, 44, 72, 52, 80, 10, 96, 5, 128, 7, 160, 11, 192, 13, 224, 14, 112, 22, 144, 26, 176, 30, 162, 15, 243, 17, 256, 19, 288, 21, 320, 23, 352, 25, 125, 50, 208, 34, 240, 38, 272, 42 (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 A285417 Rémy Sigrist, Scatterplot of the first 150000 terms EXAMPLE The first terms, alongside the primes p such that p^5 divides a(n)*a(n+1), are: n       a(n)    p --      ----    - 1       1       2 2       32      2 3       2       2 4       16      2 5       4       2 6       8       2 7       12      2 8       24      2 9       20      2 10      40      2 11      28      2 12      48      2 13      6       2 14      64      2 15      3       3 16      81      3 17      9       3 18      27      3 19      18      3 20      54      3 ... 1476    7744    2 1477    811     2, 3 1478    7776    2, 3 1479    813     3 ... CROSSREFS Cf. A285296. Sequence in context: A103325 A221760 A037932 * A303328 A298921 A070631 Adjacent sequences:  A285414 A285415 A285416 * A285418 A285419 A285420 KEYWORD nonn AUTHOR Rémy Sigrist, Apr 18 2017 STATUS approved

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Last modified December 4 02:40 EST 2021. Contains 349469 sequences. (Running on oeis4.)