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 A096101 a(1) = 1; for n > 1: a(n) = smallest number >1 such that product of any two or more successive terms - 1 is prime. 1
 1, 3, 2, 2, 2, 3, 170, 46600, 1901907, 65157236 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Next term > 20000000 if it exists. LINKS EXAMPLE a(2) is not 2 since 1*2-1 = 1 is not prime, but 1*3-1 = 2 is prime, hence a(2) = 3. a(6) is not 2 since 2*2*2*2-1 = 15 is not prime, but 2*3-1 = 5, 2*2*3-1 = 11, 2*2*2*3-1 = 23, 3*2*2*2*3-1 = 71 are all prime, hence a(6) = 3. CROSSREFS Cf. A096100. Sequence in context: A163751 A067279 A106267 * A104890 A064123 A024703 Adjacent sequences:  A096098 A096099 A096100 * A096102 A096103 A096104 KEYWORD more,nonn AUTHOR Amarnath Murthy, Jun 24 2004 EXTENSIONS Edited and extended by Klaus Brockhaus, Jul 05 2004 a(10) from Donovan Johnson, Apr 22 2008 STATUS approved

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Last modified December 15 09:05 EST 2019. Contains 329995 sequences. (Running on oeis4.)