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A093490 a(0) = 2; for n > 0, a(n) is the least prime of the form k*n*a(n-1) - 1. 3
2, 3, 5, 29, 347, 3469, 41627, 1748333, 27973327, 1007039771, 70492783969, 7754206236589, 2605413295493903, 6503111585552781887, 4825308796480164160153, 1881870430627264022459669 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
LINKS
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
KEYWORD
nonn,changed
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

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Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)