Number of primes p of the form k^2 + 1 less than 10^n such that p+2 and 2p+1 are also primes.
A356364
Number of primes p of the form k^2 + 1 less than 10^n such that p+2 and 2p+1 are also primes.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =3a(6) =7a(7) =10a(8) =18a(9) =43a(10) =86a(11) =185a(12) =449a(13) =1091a(14) =2764a(15) =6978a(16) =17951a(17) =47146a(18) =125507a(19) =337600a(20) =916229a(21) =2504458a(22) =6898908
External references
- oeis: A356364