|
|
A165781
|
|
a(n) = (2^A002326(n)-1)/(2*n+1).
|
|
7
|
|
|
1, 1, 3, 1, 7, 93, 315, 1, 15, 13797, 3, 89, 41943, 9709, 9256395, 1, 31, 117, 1857283155, 105, 25575, 381, 91, 178481, 42799, 5, 84973577874915, 19065, 4599, 4885260612740877, 18900352534538475, 1, 63, 1101298153654301589
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,3
|
|
COMMENTS
|
|
|
LINKS
|
|
|
MAPLE
|
A002326 := proc(n) if n = 0 then 1 ; else numtheory[order](2, 2*n+1) ; end if ; end proc:
|
|
MATHEMATICA
|
a[n_] := (2^MultiplicativeOrder[2, 2n+1]-1)/(2n+1);
|
|
PROG
|
(PARI) a(n)=(2^znorder(Mod(2, n=2*n+1))-1)/n \\ M. F. Hasler, Sep 20 2017
|
|
CROSSREFS
|
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
|
|
EXTENSIONS
|
Sign in definition and offset corrected by R. J. Mathar, Nov 16 2009
|
|
STATUS
|
approved
|
|
|
|