A208357 Number of meanders of order 2n+1 (4*n+2 crossings of the infinite line) with central 1-1 cut.

4, 64, 1764, 68644, 3341584, 190992400, 12310790116, 871343837764, 66469126179600, 5391179227622500

Offset

1,1

References

A. Panayotopoulos and P. Tsikouras, Properties of meanders, JCMCC 46 (2003), 181-190.

A. Panayotopoulos and P. Vlamos, Meandric Polygons, Ars Combinatoria 87 (2008), 147-159.

Links

Table of n, a(n) for n=1..10.

S. K. Lando and A. K. Zvonkin, Plane and projective meanders, Theoretical Computer Science Vol. 117, pp. 227-241, 1993.

A. Panayotopoulos and P. Tsikouras, The multimatching property of nested sets, Math. & Sci. Hum. 149 (2000), 23-30.

A. Panayotopoulos and P. Tsikouras, Meanders and Motzkin Words, J. Integer Seqs., Vol. 7, 2004.

A. Panayotopoulos and P. Vlamos, Cutting Degree of Meanders, Artificial Intelligence Applications and Innovations, IFIP Advances in Information and Communication Technology, Volume 382, 2012, pp 480-489; DOI 10.1007/978-3-642-33412-2_49. - From N. J. A. Sloane, Dec 29 2012

Formula

a(n) = b(n)^2 where b(n) = A005315 (with a different offset).

Crossrefs

Cf. A005315, A192927, A207851.

Sequence in context: A264335 A091483 A263988 * A050636 A098698 A301583

Adjacent sequences: A208354 A208355 A208356 * A208358 A208359 A208360

Keyword

nonn,more

Author

Panayotis Vlamos and Antonios Panayotopoulos, Feb 25 2012

Status

approved