A103234 Numbers k such that the k-th Euler number (A122045(k)) is prime.

4, 6, 38, 454, 510

Offset: 1

Author

Eric W. Weisstein, Jan 26 2005

Keywords

• nonn
• hard
• more

Comments

Equals 2*A014547.

No others for k <= 69574 (Simon Plouffe). - Eric W. Weisstein, Aug 24 2020

No others for k <= 112130 (Simon Plouffe). - Eric W. Weisstein, Apr 15 2024

Links

• Eric Weisstein's World of Mathematics, Euler Number
• Eric Weisstein's World of Mathematics, Euler Number Prime
• Eric Weisstein's World of Mathematics, Integer Sequence Primes

Crossrefs

Cf. A000364, A014547, A122045 (EulerE), A092823.

Programs

Mathematica

Position[EulerE[Range[600]], _?PrimeQ] // Flatten
Select[Range[600], PrimeQ @* EulerE] (* Eric W. Weisstein, Apr 12 2024 *)