login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A086783 Discriminant of the polynomial x^n - 1. 2
1, 4, -27, -256, 3125, 46656, -823543, -16777216, 387420489, 10000000000, -285311670611, -8916100448256, 302875106592253, 11112006825558016, -437893890380859375, -18446744073709551616, 827240261886336764177, 39346408075296537575424, -1978419655660313589123979 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..19.

Mohammad K. Azarian, On the Hyperfactorial Function, Hypertriangular Function, and the Discriminants of Certain Polynomials, International Journal of Pure and Applied Mathematics, Vol. 36, No. 2, 2007, pp. 249-255.  Mathematical Reviews, MR2312537.  Zentralblatt MATH, Zbl 1133.11012.

FORMULA

a(n) = (-1)^[(n-1)/2] * n^n = (-1)^[(n-1)/2] * A000312(n).

PROG

(Sage) def A086783(n) : return (-1)^((n-1)//2) * n^n # Eric M. Schmidt, May 04 2013

(PARI) a(n)=poldisc('x^n-1); \\ Joerg Arndt, May 04 2013

CROSSREFS

Cf. A000312, A004124.

Sequence in context: A245414 A000312 A177885 * A301742 A050764 A302108

Adjacent sequences:  A086780 A086781 A086782 * A086784 A086785 A086786

KEYWORD

sign,easy

AUTHOR

Yuval Dekel (dekelyuval(AT)hotmail.com), Aug 03 2003

EXTENSIONS

More terms from Eric M. Schmidt, May 04 2013

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 21 10:33 EDT 2018. Contains 316414 sequences. (Running on oeis4.)