|
Search: id:A002253
|
|
|
| A002253 |
|
Numbers n such that 3*2^n+1 is prime.
(Formerly M1318 N0506)
|
|
+0
3
|
|
| 1, 2, 5, 6, 8, 12, 18, 30, 36, 41, 66, 189, 201, 209, 276, 353, 408, 438, 534, 2208, 2816, 3168, 3189, 3912, 20909, 34350, 42294, 42665, 44685, 48150, 54792, 55182, 59973, 80190, 157169, 213321, 303093, 362765, 382449, 709968, 801978, 916773, 1832496, 2145353, 2291610, 2478785
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
Contribution from Zak Seidov (zakseidov(AT)yahoo.com), Mar 08 2009: (Start)
List is complete up to 3941000 according to the list of RB & WK.
So far there are only 4 primes: 2, 5, 41, 353. (End)
|
|
REFERENCES
|
D. E. Knuth, The Art of Computer Programming. Addison-Wesley, Reading, MA, Vol. 2, p. 614.
H. Riesel, ``Prime numbers and computer methods for factorization,'' Progress in Mathematics, Vol. 57, Birkhauser, Boston, 1985, Chap. 4, see pp. 381-384.
N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
|
|
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
|
|
CROSSREFS
|
Cf. A039687, A002254.
Sequence in context: A059009 A026179 A105107 this_sequence A032716 A132229 A028750
Adjacent sequences: A002250 A002251 A002252 this_sequence A002254 A002255 A002256
|
|
KEYWORD
|
hard,nonn
|
|
AUTHOR
|
N. J. A. Sloane (njas(AT)research.att.com).
|
|
EXTENSIONS
|
Corrected and extended according to the list of Ray Ballinger and Wilfrid Keller by Zak Seidov (zakseidov(AT)yahoo.com), Mar 08 2009
Edited by N. J. A. Sloane, Mar 13 2009
|
|
|
Search completed in 0.002 seconds
|
