A075375 Rearrangement of natural numbers so that every term is relatively prime to the sum of its neighbors.

1, 2, 4, 3, 6, 8, 5, 9, 11, 7, 12, 10, 15, 13, 14, 16, 17, 19, 18, 22, 21, 24, 20, 23, 25, 26, 28, 27, 30, 32, 29, 31, 34, 36, 33, 35, 38, 40, 39, 37, 41, 42, 44, 43, 45, 46, 48, 49, 47, 50, 52, 51, 54, 56, 53, 55, 58, 60, 61, 57, 63, 59, 62, 64, 65, 67, 66, 70, 71, 68, 72, 69

Offset

1,2

Comments

If a(n) = k, define the dislocation of k to be Absolute[k-n]. Conjecture: The maximum value of dislocation < 5.

The conjecture first fails at a(169) = 164. In the first 18000 terms, the largest dislocation is 8. - David Wasserman, Jan 17 2005

Links

Table of n, a(n) for n=1..72.

Crossrefs

Cf. A075376.

Sequence in context: A261351 A249054 A103867 * A191670 A065562 A272904

Adjacent sequences: A075372 A075373 A075374 * A075376 A075377 A075378

Keyword

nonn

Author

Amarnath Murthy, Sep 20 2002

Extensions

More terms from David Wasserman, Jan 17 2005

Status

approved