A257489 Arrange numbers in a single clockwise spiral so that each number is relatively prime to its 12 nearest neighbors.

1, 2, 3, 5, 4, 7, 9, 11, 13, 15, 17, 19, 8, 23, 29, 27, 25, 31, 37, 10, 41, 43, 14, 47, 53, 16, 49, 59, 55, 21, 61, 65, 67, 22, 71, 73, 6, 77, 79, 39, 83, 89, 12, 91, 85, 57, 97, 101, 33, 35, 103, 107, 18, 109, 113, 32, 45, 121, 119, 81, 95, 127, 131, 115, 133

Offset

1,2

Comments

In the illustration of initial terms (see Links), the 12 nearest neighbors of the first term are highlighted in yellow.

Links

Jon E. Schoenfield, Table of n, a(n) for n = 1..50000

Jon E. Schoenfield, Illustration of initial terms

Jon E. Schoenfield, Graph of first 50000 terms

Crossrefs

Cf. A064413, A257321-A257340.

Sequence in context: A322863 A081994 A249064 * A090252 A140140 A242693

Adjacent sequences: A257486 A257487 A257488 * A257490 A257491 A257492

Keyword

nonn

Author

Jon E. Schoenfield, Apr 26 2015

Status

approved