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 A182425 a(n) the largest integer K such that (prime(n+1)-1)^(2^k)+1 for 0<=k<=K is prime. 0
 4, 3, 2, 1, 0, 2, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 2, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This sequence is a generalized reference to Fermat primes. LINKS Table of n, a(n) for n=1..87. MATHEMATICA Table[k = 0; While[PrimeQ[(Prime[n+1] - 1)^(2^k) + 1], k++]; k - 1, {n, 100}] (* T. D. Noe, Apr 28 2012 *) CROSSREFS Cf. A182199. Sequence in context: A023446 A258447 A066440 * A071692 A307335 A030586 Adjacent sequences: A182422 A182423 A182424 * A182426 A182427 A182428 KEYWORD nonn AUTHOR Thomas Ordowski, Apr 28 2012 STATUS approved

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Last modified February 26 02:01 EST 2024. Contains 370335 sequences. (Running on oeis4.)