|
Search: id:A050414
|
|
|
| A050414 |
|
Numbers n such that 2^n - 3 is prime. |
|
+0
15
|
|
| 3, 4, 5, 6, 9, 10, 12, 14, 20, 22, 24, 29, 94, 116, 122, 150, 174, 213, 221, 233, 266, 336, 452, 545, 689, 694, 850, 1736, 2321, 3237, 3954, 5630, 6756, 8770, 10572, 14114, 14400, 16460, 16680, 20757, 26350, 30041, 34452, 36552, 42689, 44629, 50474
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
I found a new term in the sequence: 20757. 2^20757-3 is a probable prime with 20 iterations of Miller-Rabin test. Also I verified that there are no more primes up to and including 2^25000-3. - Dmitry Kamenetsky (dkamen(AT)rsise.anu.edu.au), Jul 12 2008
|
|
LINKS
|
PRP Top Records of this form [From M. Frind & P. Underwood, Gary Barnes (batalovs(AT)yahoo.com), Oct 20 2008]
|
|
MATHEMATICA
|
Do[ If[ PrimeQ[ 2^n -3 ], Print[n]], { n, 1, 15000 }]
|
|
CROSSREFS
|
Cf. A045768, A050415, A057732 (numbers n such that 2^n + 3 is prime).
Sequence in context: A047250 A081944 A129948 this_sequence A136681 A104373 A047427
Adjacent sequences: A050411 A050412 A050413 this_sequence A050415 A050416 A050417
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Jud McCranie (j.mccranie(AT)comcast.net), Dec 22 1999
|
|
EXTENSIONS
|
More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Sep 15 2000 and from Andrey Kulsha (Andrey_601(AT)tut.by), Feb 11 2001
a(40) from Dmitry Kamenetsky (dkamen(AT)rsise.anu.edu.au), Jul 12 2008
A new PRP term 26350 from Serge Batalov (batalovs(AT)yahoo.com), Oct 20 2008
Corrected and extended by including two smaller (apparently known) PRP and 16 larger terms from PRP Top Records of this form, all discovered by M. Frind & P. Underwood, Gary Barnes (batalovs(AT)yahoo.com), Oct 20 2008
|
|
|
Search completed in 0.002 seconds
|
