|
Search: id:A121606
|
|
|
| A121606 |
|
Indices n such that A018910[n] = (Fibonacci[n+3] + 2) are primes. |
|
+0
2
|
|
| 1, 2, 5, 11, 19, 37, 73, 85, 155, 193, 227, 233, 257, 785, 797, 1277, 2371, 2771
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
A018910[n] is Pisot sequence L(4,5). Prime Pisot L(4,5) numbers are A018910[a(n)] = Fibonacci[a(n) + 3 ] + 2 = {5,7,23,379,17713,102334157,...} = A121605[n]. Most listed a(n) are prime except a(8),a(9),a(14),a(18).
|
|
MATHEMATICA
|
Do[f=Fibonacci[n+3]+2; If[PrimeQ[f], Print[n]], {n, 1, 3000}]
|
|
CROSSREFS
|
Cf. A121605, A018910, A048584.
Sequence in context: A040105 A156768 A134694 this_sequence A166164 A097008 A051653
Adjacent sequences: A121603 A121604 A121605 this_sequence A121607 A121608 A121609
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Alexander Adamchuk (alex(AT)kolmogorov.com), Aug 09 2006
|
|
|
Search completed in 0.002 seconds
|
