

A217310


The number of meandering curves of order n, with only one extremity covered by its arcs.


3



0, 0, 4, 4, 32, 38, 264, 342, 2288, 3134, 20740, 29526, 194916, 285458, 1885840, 2822310, 18682016, 28440970, 188717116, 291294678, 1937706144, 3025232480, 20173268632, 31797822936, 212530874156, 337731551446, 2262235585956, 3620119437762, 24297593488468
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OFFSET

1,3


COMMENTS

A meandering curve of order n is a continuous curve which does not intersect itself yet intersects a horizontal line n times.


REFERENCES

A. Panayotopoulos and P. Tsikouras, Properties of meanders, JCMCC 46 (2003), 181190.


LINKS

Panayotis Vlamos, Table of n, a(n) for n = 1..42
A. Panayotopoulos, P. Vlamos, Partitioning the Meandering Curves, Mathematics in Computer Science (2015) p 110.


FORMULA

a(n) = A223093(n) * A000034(n).  Andrew Howroyd, Dec 06 2015


CROSSREFS

Cf. A005315.
Sequence in context: A270625 A271019 A271003 * A298681 A189743 A089542
Adjacent sequences: A217307 A217308 A217309 * A217311 A217312 A217313


KEYWORD

nonn


AUTHOR

Panayotis Vlamos, Antonios Panayotopoulos, Georgia Theocharopoulou, Mar 17 2013


STATUS

approved



