login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A002970 Numbers n such that 4*n^2 + 9 is prime.
(Formerly M3248)
6
1, 4, 5, 10, 16, 19, 20, 26, 29, 31, 35, 41, 44, 49, 50, 55, 56, 59, 70, 71, 80, 85, 94, 95, 100, 101, 106, 109, 110, 121, 149, 154, 160, 166, 175, 179, 184, 190, 191, 200, 205, 206, 211, 224, 236, 241, 245, 251, 256, 265, 269, 271, 284, 286, 289, 299, 304, 314 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

E. Kogbetliantz and A. Krikorian, Handbook of First Complex Prime Numbers, Gordon and Breach, NY, 1971, p. 1.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

E. Kogbetliantz and A. Krikorian Handbook of First Complex Prime Numbers, Gordon and Breach, NY, 1971 [Annotated scans of a few pages]

MATHEMATICA

Select[Range[350], PrimeQ[4 #^2 + 9] &] (* Vincenzo Librandi, Mar 19 2014 *)

PROG

(Magma)[n: n in [0..600]|IsPrime(4*n^2+9)]; // Vincenzo Librandi, Nov 21 2010

(PARI) is(n)=isprime(4*n^2+9) \\ Charles R Greathouse IV, Feb 17 2017

CROSSREFS

Sequence in context: A354968 A102006 A118735 * A073611 A058594 A285289

Adjacent sequences: A002967 A002968 A002969 * A002971 A002972 A002973

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 27 03:04 EST 2022. Contains 358362 sequences. (Running on oeis4.)