A122566 Primes with index k^2+k+1.

2, 5, 17, 41, 73, 127, 191, 269, 367, 467, 607, 751, 919, 1093, 1297, 1523, 1753, 2027, 2309, 2621, 2909, 3299, 3623, 4007, 4421, 4861, 5303, 5749, 6257, 6763, 7307, 7867, 8447, 9041, 9643, 10273, 10979, 11719, 12421, 13121, 13883, 14723, 15467, 16319

Offset

0,1

Links

Table of n, a(n) for n=0..43.

Formula

a(n) = prime(n^2+n+1). - Wesley Ivan Hurt, Nov 28 2021

Example

a(2) = 17 = P(2^2+2+1) = P(7).

Maple

seq(ithprime(k^2+k+1), k=0..60);

Mathematica

Table[Prime[k^2+k+1], {k, 0, 50}] (* Harvey P. Dale, Apr 01 2013 *)

Crossrefs

Cf. A000040.

Sequence in context: A099207 A320102 A197918 * A263638 A118500 A323427

Adjacent sequences: A122563 A122564 A122565 * A122567 A122568 A122569

Keyword

nonn

Author

Miklos Kristof, Sep 21 2006

Status

approved