|
Search: id:A020501
|
|
|
| A020501 |
|
Cyclotomic polynomials at x=-2. |
|
+0 4
|
|
| -2, -3, -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
(list; graph; listen)
|
|
|
OFFSET
|
0,1
|
|
|
COMMENT
|
a(0) depends on the definition of the 0-th cyclotomic polynomial; Maple defines it as x, but Mathematica defines it as 1. - T. D. Noe, Jul 23 2008 [a(0) = x is correct. - N. J. A. Sloane (njas(AT)research.att.com), Aug 01 2008]
A020501[2n] = A019320[n] for all odd n > 1. (Because if m > 1 is odd, then Phi_2m(x) = Phi_m(-x) as demonstrated by Bloom). - Antti Karttunen Aug 02 2001
|
|
REFERENCES
|
Bloom, D.M. "On the Coefficients of the Cyclotomic Polynomials." Amer.Math.Monthly 75, 372-377, 1968.
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=0..1000
Index entries for cyclotomic polynomials, values at X
|
|
MAPLE
|
with(numtheory, cyclotomic); f := n->subs(x=-2, cyclotomic(n, x)); seq(f(i), i=0..64);
|
|
CROSSREFS
|
Cf. A020500, A020513.
Cf. A105603
Sequence in context: A054250 A067337 A047973 this_sequence A086404 A152976 A153861
Adjacent sequences: A020498 A020499 A020500 this_sequence A020502 A020503 A020504
|
|
KEYWORD
|
sign
|
|
AUTHOR
|
Simon Plouffe (simon.plouffe(AT)gmail.com)
|
|
|
Search completed in 0.002 seconds
|