A353230 Number of Condorcet voting profiles with three candidates and 2n-1 voters where all the choices are from {123, 231, 312}.
0, 6, 90, 1050, 11130, 112266, 1099098, 10550826, 99899514, 936435786, 8711707290, 80572452714, 741766408890, 6803700252810, 62219207836890, 567597206875050, 5167463468534010, 46965976868507850, 426262280218695450, 3864157168469020650, 34994228358927126330
Offset: 1
Keywords
Links
- Shalosh B. Ekhad, More terms.
- Rebecca Embar and Doron Zeilberger, Counting Condorcet.
Crossrefs
Cf. A353194.
Programs
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Mathematica
Table[FullSimplify[3^(2*n - 1) - 2^(n-1) * Binomial[2*n, n] * Hypergeometric2F1[1, n + 1/2, n + 1, 8/9]/3], {n, 1, 25}] (* Vaclav Kotesovec, May 20 2022 *)
Formula
a(n) = ((17*n-21)*a(n-1)-(72*n-108)*a(n-2))/(n-1), with a(1) = 0, a(2) = 6.
Comments