A093490 a(0) = 2; for n > 0, a(n) is the least prime of the form k*n*a(n-1) - 1.

2, 3, 5, 29, 347, 3469, 41627, 1748333, 27973327, 1007039771, 70492783969, 7754206236589, 2605413295493903, 6503111585552781887, 4825308796480164160153, 1881870430627264022459669

Offset

0,1

Links

Harvey P. Dale, Table of n, a(n) for n = 0..200

Example

a(3) = 29, a(4) = 3*4*29 - 1 = 347.

Mathematica

nxt[{n_, a_}]:=Module[{k=1}, While[!PrimeQ[k(n+1)a-1], k++]; {n+1, k(n+1)a- 1}]; NestList[nxt, {0, 2}, 20][[All, 2]] (* Harvey P. Dale, Feb 27 2020 *)

Prog

(PARI) v=[2]; for(n=2, 20, k=1; while(!isprime(p=k*(n-1)*v[n-1]-1), k++); v=concat(v, p)); v \\ Rick L. Shepherd, Jan 31 2005

Crossrefs

Cf. A103342 (corresponding k values), A091771, A091879.

Sequence in context: A358896 A279189 A107451 * A073309 A226124 A110389

Adjacent sequences: A093487 A093488 A093489 * A093491 A093492 A093493

Keyword

nonn

Author

Amarnath Murthy, Apr 16 2004

Extensions

More terms from Rick L. Shepherd and Ryan Propper, Jan 31 2005

Edited by N. J. A. Sloane at the suggestion of Andrew S. Plewe, May 14 2007

Status

approved