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Number of nonequivalent dissections of an n-gon by nonintersecting diagonals up to rotation.
(Formerly M0909)
6

%I M0909 #22 Dec 26 2021 14:25:17

%S 1,2,3,11,29,122,479,2113,9369,43392,203595,975563,4736005,23296394,

%T 115811855,581324861,2942579633,15008044522,77064865555,398150807179,

%U 2068470765261,10800665952376,56658467018647,298489772155137,1578702640556193

%N Number of nonequivalent dissections of an n-gon by nonintersecting diagonals up to rotation.

%C Total number of dissections of an n-gon into polygons without reflection. - _Sean A. Irvine_, May 15 2015

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H Andrew Howroyd, <a href="/A003455/b003455.txt">Table of n, a(n) for n = 3..200</a>

%H P. Lisonek, <a href="http://dx.doi.org/10.1006/jsco.1995.1066">Closed forms for the number of polygon dissections</a>, Journal of Symbolic Computation 20 (1995), 595-601.

%H Ronald C. Read, <a href="http://dx.doi.org/10.1007/BF03031688">On general dissections of a polygon</a>, Aequat. math. 18 (1978) 370-388.

%o (PARI) \\ See A295495 for DissectionsModCyclic().

%o DissectionsModCyclic(apply(v->1, [1..30])) \\ _Andrew Howroyd_, Nov 22 2017

%Y Cf. A001004, A003454, A003456, A005034, A295224, A295495.

%K nonn

%O 3,2

%A _N. J. A. Sloane_

%E More terms from _Sean A. Irvine_, May 15 2015

%E Name clarified by _Andrew Howroyd_, Nov 22 2017