|
Search: id:A002254
|
|
|
| A002254 |
|
Numbers n such that 5*2^n+1 is prime.
(Formerly M2635 N1046)
|
|
+0
5
|
|
| 1, 3, 7, 13, 15, 25, 39, 55, 75, 85, 127, 1947, 3313, 4687, 5947, 13165, 23473, 26607, 40937, 125413, 209787, 240937, 819739, 1320487
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
REFERENCES
|
H. Riesel, ``Prime numbers and computer methods for factorization,'' Progress in Mathematics, Vol. 57, Birkhauser, Boston, 1985, Chap. 4, see pp. 381-384.
R. M. Robinson, A report on primes of the form k.2^n+1 and on factors of Fermat numbers, Proc. Amer. Math. Soc., 9 (1958), 673-681.
|
|
LINKS
|
Ray Ballinger, Proth Search Page
Ray Ballinger and Wilfrid Keller, List of primes k.2^n + 1 for k < 300
C. K. Caldwell, The Prime Pages
Y. Gallot, Proth.exe: Windows Program for Finding Large Primes
Wilfrid Keller, List of primes k.2^n - 1 for k < 300
Eric Weisstein's World of Mathematics, Proth Prime
Index entries for sequences of n such that k*2^n-1 (or k*2^n+1) is prime
|
|
MATHEMATICA
|
lst={}; Do[If[PrimeQ[5*2^n+1], AppendTo[lst, n]], {n, 0, 2*10^3}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Aug 19 2008]
|
|
CROSSREFS
|
Cf. A050526.
Sequence in context: A092734 A002236 A080565 this_sequence A060657 A117533 A065057
Adjacent sequences: A002251 A002252 A002253 this_sequence A002255 A002256 A002257
|
|
KEYWORD
|
hard,nonn
|
|
AUTHOR
|
njas
|
|
|
Search completed in 0.002 seconds
|
