A102738 Numbers k such that 4*10^k - 11 is prime.

1, 2, 3, 4, 5, 15, 35, 61, 256, 357, 628, 767, 1064, 1096, 6608, 14821, 15341, 18795, 22648, 24199, 31919, 38519, 44279

Offset: 1

Author

Tom Mueller (muel4503(AT)uni-trier.de), Feb 08 2005

Keywords

• more
• nonn

Comments

Numbers corresponding to terms <= 767 are certified primes. - Klaus Brockhaus, Feb 16 2005

The next term is larger than 2500. - Stefan Steinerberger, Feb 18 2006

Programs

Mathematica

For[n=1, n<2500,n++,If[PrimeQ[4*10^n-11], Print[n]]] (* Stefan Steinerberger, Feb 18 2006 *)

PARI

is(n)=ispseudoprime(4*10^n-11) \\ Charles R Greathouse IV, Jun 13 2017

Extensions

a(9)-a(14) from Klaus Brockhaus, Feb 16 2005

a(15) from Ryan Propper, Jul 21 2006

a(16)-a(17) from Michael S. Branicky, May 01 2023

a(18)-a(23) from Kamada data by Tyler Busby, May 03 2024