

A290646


Number of dissections of an ngon into 3 and 4gons counted up to rotations and reflections.


4



1, 2, 2, 7, 14, 53, 171, 691, 2738, 11720, 50486, 224012, 1005468, 4581815, 21093190, 98093226, 459986674, 2173599817, 10340539744, 49496519950, 238240366274, 1152543685463, 5601603835982, 27341242042238, 133977037982121, 658902522544060, 3251446102879398
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OFFSET

3,2


LINKS



EXAMPLE

For a(5) = 2 the dissections of a pentagon are: a dissection into 3 triangles; a dissection into one triangle and one quadrangle.


MATHEMATICA

(* See A295419 for DissectionsModDihedral. *)


PROG

(PARI) \\ See A295419 for DissectionsModDihedral.
DissectionsModDihedral(apply(v>v==3v==4, [1..25])) \\ Andrew Howroyd, Nov 22 2017


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



