|
| |
|
|
A105603
|
|
Sylvester-Jacobsthal cyclotomic numbers.
|
|
3
| |
|
|
1, 1, 3, 5, 11, 7, 43, 17, 57, 31, 683, 13, 2731, 127, 331, 257, 43691, 73, 174763, 205, 5419, 2047, 2796203, 241, 1016801, 8191, 261633, 3277, 178956971, 151, 715827883, 65537, 1397419, 131071, 24214051, 4033, 45812984491, 524287, 22366891, 61681
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,3
|
|
|
COMMENTS
| Primitive parts of Jacobsthal numbers A001045.
|
|
|
LINKS
| T. D. Noe, Table of n, a(n) for n=1..1000
Eric Weisstein's World of Mathematics, Sylvester Cyclotomic Number.
|
|
|
FORMULA
| a(n)=product{k=1..n-1, if(gcd(n, k)=1, 2+exp(2*pi*I*k/n), 1)}, I=sqrt(-1)
|
|
|
CROSSREFS
| Cf. A020501.
Sequence in context: A087322 A094747 A129738 * A170835 A122133 A065019
Adjacent sequences: A105600 A105601 A105602 * A105604 A105605 A105606
|
|
|
KEYWORD
| easy,nonn
|
|
|
AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Apr 15 2005
|
| |
|
|
