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 A090874 a(n) is the smallest number m such that m^2^k + (m+1)^2^k is prime for k=0,1,...,n. 2
 1, 1, 1, 1, 1, 1806390369 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,6 COMMENTS The first five terms of this sequence correspond to Fermat primes. LINKS EXAMPLE a(5)=1806390369 because 1806390369 is the smallest number m such that m^2^k+(m+1)^2^k is prime for k=0,1,2,3,4 and 5. CROSSREFS Cf. A090872, A090873, A019434, A000215. Sequence in context: A129616 A105006 A318788 * A071371 A052094 A256123 Adjacent sequences:  A090871 A090872 A090873 * A090875 A090876 A090877 KEYWORD nonn AUTHOR Farideh Firoozbakht, Feb 06 2004 STATUS approved

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Last modified December 10 20:36 EST 2019. Contains 329909 sequences. (Running on oeis4.)