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 A303839 Number of noncrossing path sets on n nodes up to rotation and reflection with each path having at least two nodes. 6

%I

%S 1,0,1,1,3,5,17,40,138,430,1546,5478,20525,77310,298301,1161692,

%T 4583525,18239037,73221198,296046399,1205038270,4933969005,

%U 20311807087,84029440358,349201537324,1457205298510,6104204225832,25661191956781,108231773165825

%N Number of noncrossing path sets on n nodes up to rotation and reflection with each path having at least two nodes.

%H Andrew Howroyd, <a href="/A303839/b303839.txt">Table of n, a(n) for n = 0..200</a>

%e Case n=4: There are 3 possibilities:

%e .

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

%e | | /

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

%e .

%o (PARI) \\ See A303731 for NCPathSetsModDihedral

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

%Y Cf. A303730, A303731, A303835, A303844.

%K nonn

%O 0,5

%A _Andrew Howroyd_, May 01 2018

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Last modified May 16 23:46 EDT 2021. Contains 343957 sequences. (Running on oeis4.)