login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A096195 a(n) = number of distinct solutions to the set of equations 1 +- x +- x^2 +- ... +- x^n = 0 over the complex numbers. 1
2, 8, 16, 64, 106, 324, 696, 1856, 4046, 10240, 19084, 49152, 98110, 218140, 464084, 1047744, 2123446, 4718592, 9632740, 20666444 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
a(2) = 8 because the set of equations 1 +- x +- x^2 = 0 generates 8 distinct solutions.
MATHEMATICA
a[n_] := a[n] = Length[Union[ Flatten[x /. Table[Solve[1 + Sum[(-1)^IntegerDigits[k, 2, n + 1][[p + 1]]x^p, {p, n}] == 0], {k, 0, 2^n - 1}]]]]; Table[a[n], {n, 10}]
CROSSREFS
Cf. A036289 (total number of solutions to the equations).
Sequence in context: A100243 A026523 A066792 * A094014 A098232 A354275
KEYWORD
more,nonn
AUTHOR
Josh Locker (jlocker(AT)mail.rochester.edu), Jul 26 2004
EXTENSIONS
More terms from Robert G. Wilson v and Labos Elemer, Jul 27 2004
a(17)-a(19) from Robert G. Wilson v, May 05 2013
a(20) from Robert G. Wilson v, May 05 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)