|
Search: id:A090534
|
|
|
| A090534 |
|
Least n-digit prime in which every two digit string is also a prime, or 0 if no such number exists. ((n-1) two digit string primes occur.). |
|
+0
1
|
|
| 2, 11, 113, 1117, 11113, 111119, 1111379, 11111117, 111111113, 1111111973, 11111111113, 111111111379, 1111111111717, 11111111111719, 111111111111713, 1111111111111319, 11111111111111119, 111111111111111131
(list; graph; listen)
|
|
|
OFFSET
|
2,1
|
|
|
COMMENT
|
Conjecture: sequence is infinite. Note:(1); If n==1 (mod 3) then in most cases a(n) is a permutation of (n-1), 1's and a 7, else a(n) is a digit permutation of (n-1) ones and a 3. (2): Obviously all the digits except the most significant one must be odd.
|
|
EXAMPLE
|
a(5) =11113 in which 11,11,11,13 are the two digit string primes.
|
|
CROSSREFS
|
Sequence in context: A099933 A098437 A069574 this_sequence A130222 A057076 A118794
Adjacent sequences: A090531 A090532 A090533 this_sequence A090535 A090536 A090537
|
|
KEYWORD
|
base,nonn
|
|
AUTHOR
|
Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Dec 08 2003
|
|
EXTENSIONS
|
More terms from David Wasserman (wasserma(AT)spawar.navy.mil), Dec 21 2005
|
|
|
Search completed in 0.002 seconds
|
