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 A303835 Number of noncrossing path sets on n nodes up to rotation and reflection with isolated vertices allowed. 3

%I

%S 1,1,2,3,8,19,64,212,833,3360,14476,63848,289892,1338000,6275589,

%T 29791100,142973014,692507861,3382070233,16638445745,82395500651,

%U 410463736691,2055858519575,10347925039015,52321093290715,265648012207312,1353953547877556,6925400869302520

%N Number of noncrossing path sets on n nodes up to rotation and reflection with isolated vertices allowed.

%H Andrew Howroyd, <a href="/A303835/b303835.txt">Table of n, a(n) for n = 0..200</a>

%e Case n=3: There are 3 possibilities:

%e .

%e o o o

%e / \

%e o o o---o o o

%e .

%e Case n=4: There are 8 possibilities:

%e .

%e o o o o o o o o o o o---o o o o---o

%e / | / | | /

%e o o o---o o o o---o o---o o---o o---o o---o

%e .

%o (PARI) \\ See A303731 for NCPathSetsModDihedral

%o Vec(NCPathSetsModDihedral(vector(30, k, 1)))

%Y Cf. A303731, A303839.

%K nonn

%O 0,3

%A _Andrew Howroyd_, May 01 2018

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Last modified October 18 18:56 EDT 2019. Contains 328197 sequences. (Running on oeis4.)