|
Search: id:A138067
|
|
|
| A138067 |
|
Least k>1 such that (2n-1)^k + 2 is prime, or 0 if no such number exists. |
|
+0
2
|
|
| 2, 2, 3, 0, 2, 5, 0, 2, 105, 0, 2, 11, 0, 5, 3, 0, 2, 15, 0, 2, 9, 0, 2, 113, 0, 5, 7, 0, 2, 27, 0, 3, 3, 0, 3, 3, 0, 12, 61, 0, 2, 3, 0, 4, 255, 0, 8, 63, 0, 2, 9, 0, 2, 3473, 0, 2, 3, 0, 2, 15, 0, 2, 87, 0, 3, 23, 0, 36, 1861, 0, 4, 3, 0, 2, 5, 0, 3, 7, 0, 136, 425, 0, 11
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
a(3n+1) = 0 for n>0.
a(54) is currently unknown.
a(84) > 30000. [From Donovan Johnson (donovan.johnson(AT)yahoo.com), Oct 29 2008]
|
|
CROSSREFS
|
Cf. A084713 = Smallest prime of the form (2n-1)^k + 2, or 0 if no such number exists. Cf. A138066 = Least k>0 such that (2n-1)^k + 2 is prime, or 0 if no such number exists. Cf. A051783 = Numbers n such that 3^n + 2 is prime. Cf. A087885 = Numbers n such that 5^n + 2 is prime. Cf. A090649, A109076, A113480, A138048, A138049, A138050, A138051, A087886, A113481.
Sequence in context: A071479 A091426 A053761 this_sequence A125093 A103516 A129234
Adjacent sequences: A138064 A138065 A138066 this_sequence A138068 A138069 A138070
|
|
KEYWORD
|
hard,more,nonn
|
|
AUTHOR
|
Alexander Adamchuk (alex(AT)kolmogorov.com), Mar 02 2008
|
|
EXTENSIONS
|
a(54)-a(83) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Oct 29 2008
|
|
|
Search completed in 0.002 seconds
|
