A085875 Rearrangement of natural numbers as follows: a(1) = 1, a(2) = 2, a(n+1) = smallest number not included earlier such that a(n-1)*a(n) + a(n+1) is a prime.

1, 2, 3, 5, 4, 9, 7, 8, 11, 13, 6, 19, 17, 14, 25, 23, 12, 31, 29, 20, 21, 37, 10, 27, 41, 16, 35, 33, 26, 49, 15, 22, 43, 45, 38, 67, 47, 18, 61, 53, 24, 55, 79, 28, 39, 59, 32, 63, 65, 34, 57, 73, 40, 51, 71, 50, 81, 77, 62, 87, 83, 76, 89, 69, 56, 103, 75, 64, 109, 93, 44, 85

Offset

1,2

Links

Sean A. Irvine, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A086553, A086554.

Sequence in context: A119475 A096116 A259431 * A330615 A302850 A338253

Adjacent sequences: A085872 A085873 A085874 * A085876 A085877 A085878

Keyword

nonn,changed

Author

Amarnath Murthy, Jul 07 2003

Extensions

Corrected and extended by Ray Chandler, Jul 08 2003

Status

approved