Smallest number k such that M(n)^2-k*M(n)-1 is prime with M(n) = Mersenne primes = A000668(n).
A139424
Smallest number k such that M(n)^2-k*M(n)-1 is prime with M(n) = Mersenne primes = A000668(n).
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =43a(6) =1a(7) =41a(8) =53a(9) =91a(10) =317a(11) =317a(12) =43a(13) =1a(14) =37a(15) =3595a(16) =563a(17) =17239a(18) =911a(19) =11497a(20) =58501a(21) =1259a(22) =10283a(23) =138569a(24) =72247a(25) =27733a(26) =11777a(27) =179105
External references
- oeis: A139424