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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

Index entries for sequences that are permutations of the natural numbers

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.)