The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A300329 Number of solutions to +-1 +- 2 +- 3 +- ... +- n == n-1 (mod n). 2
 2, 4, 2, 0, 6, 20, 18, 0, 56, 204, 186, 0, 630, 2340, 2182, 0, 7710, 29120, 27594, 0, 99858, 381300, 364722, 0, 1342176, 5162220, 4971008, 0, 18512790, 71582716, 69273666, 0, 260300986, 1010580540, 981706806, 0, 3714566310, 14467258260, 14096302710, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Seiichi Manyama, Table of n, a(n) for n = 1..3333 EXAMPLE Solutions for n = 7: -------------------------------------------------------------- 1 +2 +3 +4 -5 -6 +7 =   6,         -1 +2 +3 -4 +5 -6 +7 =   6, 1 +2 +3 +4 -5 -6 -7 =  -8,         -1 +2 +3 -4 +5 -6 -7 =  -8, 1 +2 +3 -4 +5 +6 +7 =  20,         -1 +2 -3 +4 +5 +6 +7 =  20, 1 +2 +3 -4 +5 +6 -7 =   6,         -1 +2 -3 +4 +5 +6 -7 =   6, 1 +2 -3 -4 -5 -6 +7 =  -8,         -1 -2 +3 -4 -5 -6 +7 =  -8, 1 +2 -3 -4 -5 -6 -7 = -22,         -1 -2 +3 -4 -5 -6 -7 = -22, 1 -2 +3 -4 -5 +6 +7 =   6,         -1 -2 -3 +4 -5 +6 +7 =   6, 1 -2 +3 -4 -5 +6 -7 =  -8,         -1 -2 -3 +4 -5 +6 -7 =  -8, 1 -2 -3 +4 +5 -6 +7 =   6, 1 -2 -3 +4 +5 -6 -7 =  -8. PROG (PARI) a(n) = my (v=vector(n, k, k==1)); for (p=1, n, v = vector(n, k, v[1+(k-1+p)%n]+v[1+(k-1-p)%n])); v[1+(n-1)%n] \\ Rémy Sigrist, Mar 03 2018 CROSSREFS Cf. A300190, A300328. Sequence in context: A127278 A335764 A202069 * A094239 A273240 A201316 Adjacent sequences:  A300326 A300327 A300328 * A300330 A300331 A300332 KEYWORD nonn AUTHOR Seiichi Manyama, Mar 03 2018 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified August 6 12:33 EDT 2020. Contains 336246 sequences. (Running on oeis4.)