login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual Appeal: Please make a donation (tax deductible in USA) to keep the OEIS running. Over 5000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A092057 Primes of the form 2*p^2 - 1, where p is prime. 9
7, 17, 97, 241, 337, 577, 3361, 3697, 6961, 10657, 23761, 25537, 32257, 37537, 49297, 64081, 65521, 77617, 79201, 89041, 126001, 138337, 153457, 171697, 193441, 249217, 269377, 287281, 334561, 351121, 374977, 474337, 633937, 652081, 665857 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

MATHEMATICA

lst={}; Do[p=Prime[n]; If[PrimeQ[r=2*p^2-1], AppendTo[lst, r]], {n, 6!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jun 20 2009 *)

PROG

(PARI) for (i=1, 300, if(isprime(2*prime(i)^2-1), print1(2*prime(i)^2-1, ", ")))

CROSSREFS

Cf. A092058.

Cf. A106483 (primes p such that 2p^2 - 1 is also prime).

Sequence in context: A177123 A124165 A239150 * A082738 A092340 A181605

Adjacent sequences:  A092054 A092055 A092056 * A092058 A092059 A092060

KEYWORD

easy,nonn

AUTHOR

Mohammed Bouayoun (mohammed.bouayoun(AT)sanef.com), Feb 19 2004

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified December 10 11:36 EST 2016. Contains 279001 sequences.