A303835 Number of noncrossing path sets on n nodes up to rotation and reflection with isolated vertices allowed.
1, 1, 2, 3, 8, 19, 64, 212, 833, 3360, 14476, 63848, 289892, 1338000, 6275589, 29791100, 142973014, 692507861, 3382070233, 16638445745, 82395500651, 410463736691, 2055858519575, 10347925039015, 52321093290715, 265648012207312, 1353953547877556, 6925400869302520
Offset: 0
Keywords
Examples
Case n=3: There are 3 possibilities: . o o o / \ o o o---o o o . Case n=4: There are 8 possibilities: . o o o o o o o o o o o---o o o o---o / | / | | / o o o---o o o o---o o---o o---o o---o o---o .
Links
- Andrew Howroyd, Table of n, a(n) for n = 0..200
Programs
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PARI
\\ See A303731 for NCPathSetsModDihedral Vec(NCPathSetsModDihedral(vector(30, k, 1)))