A109807 - OEIS

A109807

Numbers n such that n^2 + 1 is a Chen prime.

1, 2, 4, 6, 10, 14, 16, 20, 24, 26, 36, 40, 56, 66, 74, 94, 116, 120, 130, 134, 146, 160, 170, 176, 204, 230, 250, 256, 260, 284, 314, 326, 340, 350, 386, 406, 430, 440, 444, 464, 466, 470, 490, 496, 536, 556, 570, 584, 634, 646, 654, 680, 686, 700, 704, 714

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Range[800], PrimeQ[#^2+1]&&PrimeOmega[#^2+3]<3&] (* Harvey P. Dale, May 07 2015 *)

PROG

(PARI) is(n)=isprime(n^2+1) && bigomega(n^2+3)<3 \\ Charles R Greathouse IV, Aug 19 2015

CROSSREFS

Subsequence of A005574.

Cf. A005574, A109611.