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A360517
Number of 2-color vertex orderings of the labeled cycle graph on 2*n vertices.
4
0, 24, 480, 18816, 1175040, 107796480, 13630955520, 2273062256640, 483283797147648, 127601594573783040, 40960778432654868480, 15710045049427958169600, 7095139411569155034316800, 3726944074638630907382071296, 2252901869996867025766994411520, 1552830650080006456164417892515840
OFFSET
1,2
COMMENTS
Bouwer and Star give a recurrence.
REFERENCES
Bouwer, I., and Z. Star. "A question of protocol." The American mathematical monthly 95.2 (1988): 118-121. See C(n).
LINKS
FORMULA
a(n) = 4*n*(n - 1)*(2*n - 1)*A360514(2*n - 3) for n > 1. - Andrew Howroyd, Feb 27 2023
PROG
(PARI) \\ Needs A360514seq from A360514.
seq(n) = {my(v=A360514seq(2*n-1)); vector(n, n, if(n>1, 4*n*(n-1)*(2*n-1)*v[2*n-3]))} \\ Andrew Howroyd, Feb 27 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Feb 27 2023.
EXTENSIONS
Terms a(6) and beyond from Andrew Howroyd, Feb 27 2023
STATUS
approved