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A093490
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a(0) = 2; for n > 0, a(n) is the least prime of the form k*n*a(n-1) - 1.
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3
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2, 3, 5, 29, 347, 3469, 41627, 1748333, 27973327, 1007039771, 70492783969, 7754206236589, 2605413295493903, 6503111585552781887, 4825308796480164160153, 1881870430627264022459669
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OFFSET
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0,1
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LINKS
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EXAMPLE
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a(3) = 29, a(4) = 3*4*29 - 1 = 347.
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MATHEMATICA
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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 *)
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PROG
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(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
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CROSSREFS
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KEYWORD
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nonn,changed
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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