A084714 a(n) = smallest prime of the form (2n-1)^k - 2, or 0 if no such number exists.

0, 7, 3, 5, 7, 14639, 11, 13, 24137567, 17, 19, 480250763996501976790165756943039, 23, 727, 839, 29, 31, 1223, 1367, 37, 2825759, 41, 43, 2207, 47, 45767944570399, 7890479, 53, 1176246293903439667999, 12117359, 59, 61, 318644812890623

Offset: 1

Author

Amarnath Murthy, Jun 10 2003

Keywords

• nonn

Crossrefs

Cf. A084712, A084713.

Programs

Mathematica

f[n_] := Block[{k = 1}, While[ !PrimeQ[(2*n - 1)^k - 2], k++ ]; (2*n - 1)^k - 2]; Table[ f[n], {n, 2, 34}]

Extensions

Edited, corrected and extended by Robert G. Wilson v, Jun 11 2003