A357056 Integers k such that k^k + k^2 + 2*k + 1 is prime.

0, 1, 2, 3, 4, 9, 10, 13, 15, 24

Offset

1,3

Comments

The next prime (if any) is unknown, but it must exceed 2000^2000 + 2000^2 + 2*2000 + 1 (a 6603-digit number).

a(11) > 15000, if it exists. - Michael S. Branicky, Sep 17 2024

Links

Table of n, a(n) for n=1..10.

Example

If k = 2, then k^k + k^2 + k*2 + 1 = 2^2 + 2^2 + 2*2 + 1 = 13, which is prime.

Crossrefs

Cf. A058912, A187605, A231712.

Sequence in context: A073338 A200260 A190119 * A273907 A066105 A083180

Adjacent sequences: A357053 A357054 A357055 * A357057 A357058 A357059

Keyword

nonn,more,hard

Author

Marco Ripà, Sep 10 2022

Status

approved