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 A111671 Smallest prime p > 3 such that p-1 has a prime factor > (p-1)^(n/(n+1)). 1
 7, 11, 23, 47, 83, 167, 263, 563, 1187, 2063, 4127, 8423, 16487, 32843, 65543, 131267, 262643, 524387, 1048703, 2097779, 4195259, 8389163, 16777907, 33554519, 67109543, 134217827, 268436867 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(1) = 7 = A111668(1). Conjectures: (1) This is a subsequence of the safe primes (A005385), (2) lim{n --> oo}(a(n+1)/a(n)) = 2. LINKS Table of n, a(n) for n=1..27. CROSSREFS Cf. A111668, A005385 (safe primes). Sequence in context: A107133 A079138 A163848 * A213895 A140111 A118072 Adjacent sequences: A111668 A111669 A111670 * A111672 A111673 A111674 KEYWORD nonn AUTHOR Rick L. Shepherd, Aug 15 2005 STATUS approved

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Last modified May 30 13:17 EDT 2023. Contains 363050 sequences. (Running on oeis4.)