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 A109807 Numbers n such that n^2 + 1 is a Chen prime. 1
 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. Sequence in context: A066755 A089238 A005574 * A259645 A191113 A125964 Adjacent sequences:  A109804 A109805 A109806 * A109808 A109809 A109810 KEYWORD nonn AUTHOR Jason Earls, Aug 16 2005 STATUS approved

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Last modified December 5 05:51 EST 2020. Contains 338944 sequences. (Running on oeis4.)