login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A128968 a(n) is the n-th prime of the form x^2+n. 0
2, 3, 19, 53, 2309, 967, 151, 6569, 3373, 2819, 15887, 2221, 3613, 81239, 4639, 6257, 101141, 6907, 35363, 106949, 59557, 6911, 49307, 70249, 10429, 408347, 33151, 9437, 518429, 63031, 40031, 159233, 155269, 66083, 725939, 156061, 13033, 641639 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..38.

EXAMPLE

a(4)=53 because 5=1^2+4,13=3^2+4, 29=5^2+4, 53=7^2+4 are prime and 53 is the 4th such prime.

MATHEMATICA

Table[Select[Range[0, 1000]^2+n, PrimeQ][[n]], {n, 40}] (* Harvey P. Dale, Aug 30 2016 *)

CROSSREFS

Sequence in context: A248702 A171149 A157042 * A153409 A143893 A262957

Adjacent sequences:  A128965 A128966 A128967 * A128969 A128970 A128971

KEYWORD

nonn

AUTHOR

John L. Drost, Apr 28 2007

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 26 05:10 EST 2020. Contains 331273 sequences. (Running on oeis4.)