A235939 Number of circular permutations with exactly one (unspecified) increasing or decreasing modular 3-sequence, with clockwise and counterclockwise traversals not counted as distinct.
0, 0, 0, 0, 5, 12, 77, 496, 3672, 30560, 284031, 2913624, 32724939, 399561428, 5270747880, 74717040128, 1132896574609, 18297399806532, 313634823814769, 5686864630734840, 108757303793301240
Offset: 1
Keywords
Examples
a(5) = 5: 12354, 23415, 34521, 45132, 51243.
References
- Paul J. Campbell, Circular permutations with exactly one modular run (3-sequence), submitted to Journal of Integer Sequences
Links
- Wayne M. Dymáček and Isaac Lambert, Circular permutations avoiding runs of i, i+1, i+2 or i, i-1, i-2, Journal of Integer Sequences, Vol. 14 (2011) Article 11.1.6.
Crossrefs
Formula
a(n) = n*A235937(n).
Extensions
a(20)-a(21) from Alois P. Heinz, Jan 24 2014
Obsolete b-file deleted by N. J. A. Sloane, Jan 05 2019
Comments