|
|
A038699
|
|
Smallest prime of form n*2^m-1, m >= 0, or 0 if no such prime exists.
|
|
16
|
|
|
3, 3, 2, 3, 19, 5, 13, 7, 17, 19, 43, 11, 103, 13, 29, 31, 67, 17, 37, 19, 41, 43, 367, 23, 199, 103, 53, 223, 463, 29, 61, 31, 131, 67, 139, 71, 73, 37, 311, 79, 163, 41, 5503, 43, 89, 367, 751, 47, 97, 199, 101, 103, 211, 53, 109, 223, 113, 463, 241663, 59, 487, 61
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
LINKS
|
|
|
MATHEMATICA
|
getm[n_]:=Module[{m=0}, While[!PrimeQ[n 2^m-1], m++]; n 2^m-1]; Array[getm, 80] (* Harvey P. Dale, Apr 24 2011 *)
|
|
PROG
|
(Haskell)
a038699 = until ((== 1) . a010051) ((+ 1) . (* 2)) . (subtract 1)
|
|
CROSSREFS
|
Primes arising in A040081 (or 0 if no prime exists).
|
|
KEYWORD
|
nonn,easy,nice
|
|
AUTHOR
|
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|