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 A085013 a(1) = 1; for n>1, a(n) = smallest prime > a(n-1) such that a(1)*...*a(n) + 2 is a prime. 3
 1, 3, 5, 7, 13, 23, 29, 37, 43, 61, 73, 89, 137, 151, 167, 199, 269, 383, 397, 521, 619, 659, 739, 1217, 1307, 1613, 1741, 1847, 1873, 2039, 2473, 2521, 2531, 3011, 3391, 3637, 3793, 4201, 4751, 5039, 5879, 6299, 7307, 7829, 8243, 8933, 9781, 9829, 10069 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS MATHEMATICA a[1] = 1; a[n_] := a[n] = Block[{k = a[n - 1] + 2}, While[ !PrimeQ[k] || ! PrimeQ[ k * Times @@ Table[ a[i], {i, 1, n - 1}] + 2], k += 2]; k]; Table[ a[n], {n, 1, 49}] CROSSREFS Cf. A083566. Sequence in context: A060274 A005235 A107664 * A164939 A125272 A127443 Adjacent sequences:  A085010 A085011 A085012 * A085014 A085015 A085016 KEYWORD nonn AUTHOR Robert G. Wilson v, Jun 17 2003 STATUS approved

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Last modified December 10 23:33 EST 2018. Contains 318049 sequences. (Running on oeis4.)