|
Search: id:A129832
|
|
|
| A129832 |
|
Integers n such that the n-th cyclotomic polynomial Phi(n) is irreducible over GF(2). |
|
+0
1
|
|
| 1, 2, 3, 5, 6, 9, 10, 11, 13, 18, 19, 22, 25, 26, 27, 29, 37, 38, 50, 53, 54, 58, 59, 61, 67, 74, 81, 83, 101, 106, 107, 118, 121, 122, 125, 131, 134, 139, 149, 162, 163, 166, 169, 173, 179, 181, 197
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
FORMULA
|
This sequence consists of 1, 2, and numbers having primitive root 2 (that is, numbers that are powers of primes p in sequence A001122, or twice powers of p). - T. D. Noe (noe(AT)sspectra.com), Jan 03 2008
|
|
EXAMPLE
|
7 is absent from the list as Phi(7) == (x^3 + x + 1)*(x^3 + x^2 + 1) (mod 2)
|
|
PROGRAM
|
(PARI) for(x=1, 200, if(polisirreducible(Mod(1, 2)*polcyclo(x)), print1(x", ")))
|
|
CROSSREFS
|
Sequence in context: A047449 A107040 A045989 this_sequence A018762 A059746 A024620
Adjacent sequences: A129829 A129830 A129831 this_sequence A129833 A129834 A129835
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Phil Carmody (pc+oeis(AT)asdf.org), May 21 2007
|
|
|
Search completed in 0.002 seconds
|
