A094753 Largest k such that (2n-1)/k + 2 as well as (2n-1)k + 2 are prime, or 0 if no such number exists.

1, 3, 1, 0, 9, 1, 0, 15, 1, 0, 21, 0, 5, 3, 1, 0, 33, 1, 0, 39, 1, 0, 45, 0, 0, 1, 0, 11, 57, 1, 0, 7, 1, 0, 1, 1, 0, 25, 7, 0, 81, 0, 17, 3, 0, 0, 0, 1, 0, 99, 1, 0, 105, 1, 0, 111, 0, 23, 117, 0, 0, 123, 1, 0, 1, 0, 0, 15, 1, 0, 0, 13, 5, 147, 1, 0, 3, 1, 0, 53, 1, 0, 15, 0, 0, 171, 0, 5, 1, 1, 0

Offset

1,2

Comments

Subsidiary sequence: Indices of 0's in the above sequence.

Links

Robert Gerbicz, Aug 22 2006, Table of n, a(n) for n = 1..152

Crossrefs

Cf. A094752.

Sequence in context: A299614 A135871 A126178 * A355350 A221713 A261765

Adjacent sequences: A094750 A094751 A094752 * A094754 A094755 A094756

Keyword

nonn

Author

Amarnath Murthy, May 29 2004

Extensions

More terms from Robert Gerbicz, Aug 22 2006

Status

approved