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URL: https://oeis.org/A377502

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A377502
Number of minimum distinguishing labelings in the cycle graph C_n.
1
6, 24, 120, 12, 28, 96, 252, 600, 1364, 3048, 6552, 13804, 29040, 59520, 122400, 248472, 504868, 1017840, 2054388, 4126100, 8294444, 16628160, 33349800, 66784536, 133775712, 267736392, 535920696, 1072242540, 2145452092, 4291768320, 8585609340, 17173070880, 34350563940
OFFSET
3,1
COMMENTS
The distinguishing number of the n-cycle graph is 3 for n = 3, 4, 5 and 2 for n >= 6.
LINKS
Eric Weisstein's World of Mathematics, Cycle Graph.
Eric Weisstein's World of Mathematics, Distinguishing Number.
FORMULA
a(n) = 2*n*A032239(n) for n >= 6. - Andrew Howroyd, May 27 2025
PROG
(PARI) a(n)={2*n*if(n<6, if(n>2, [1, 3, 12][n-2]), sumdiv(n, d, moebius(n/d)*(2^d/n - if(d%2, 2^((d+1)/2), 3*2^(d/2)/2)))/2)} \\ Andrew Howroyd, May 27 2025
CROSSREFS
Cf. A032239.
Sequence in context: A293236 A217193 A109583 * A352807 A100934 A127917
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Oct 30 2024
EXTENSIONS
a(27) onwards from Andrew Howroyd, May 27 2025
STATUS
approved