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 A143385 Least a(n) such that M(n)*(M(n)+a(n))-1 and M(n)*(M(n)+a(n))+1 are twin primes with M(i)=i-th Mersenne prime. 3
 1, 53, 11, 17, 317, 89, 737, 2543, 1247, 6209, 15107, 33119, 60611, 671063, 2648057 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Table of n, a(n) for n=1..15. EXAMPLE (2^2-1)*(2^2-1+1)-1=11 prime, 11 and 13 twin primes, 2^2-1=M(1) so a(1)=1 CROSSREFS Cf. A139426. Sequence in context: A078681 A143294 A143428 * A231426 A298061 A297984 Adjacent sequences: A143382 A143383 A143384 * A143386 A143387 A143388 KEYWORD hard,more,nonn AUTHOR Pierre CAMI, Aug 11 2008 STATUS approved

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Last modified December 5 21:07 EST 2023. Contains 367594 sequences. (Running on oeis4.)