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A303844
Number of noncrossing path sets on n nodes up to rotation with each path having at least two nodes.
6
1, 0, 1, 1, 4, 7, 26, 69, 246, 818, 2976, 10791, 40591, 153959, 594753, 2320696, 9159498, 36467012, 146411208, 592046830, 2409946566, 9867745442, 40623068380, 168058068487, 698400767839, 2914407151002, 12208398647345, 51322369218674, 216463504458521
OFFSET
0,5
LINKS
EXAMPLE
Case n=4: There are 4 possibilities:
.
o---o o o o---o o---o
| | / \
o---o o---o o---o o---o
.
PROG
(PARI) \\ See A303732 for NCPathSetsModCyclic
Vec(NCPathSetsModCyclic(vector(30, k, k>1)))
CROSSREFS
KEYWORD
nonn
AUTHOR
Andrew Howroyd, May 01 2018
STATUS
approved