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A369474
Number of chiral pairs of polyominoes composed of n pentachoral cells of the hyperbolic regular tiling with Schläfli symbol {3,3,3,oo}.
1
0, 0, 0, 0, 1, 10, 80, 611, 4602, 34791, 265606, 2054034, 16094883, 127693729, 1024649237, 8306343347, 67952829212, 560471786912, 4656785469564, 38948533963500, 327715193729107, 2772468576820531
OFFSET
1,6
COMMENTS
Also number of chiral pairs of simplicial 4-clusters or stack polytopes with n pentachoral cells. Each member of a chiral pair is a reflection but not a rotation of the other. Some of the h(4,n) terms in the Hering article are in error, including the 6th, 8th and 9th.
LINKS
F. Hering et al., The enumeration of stack polytopes and simplicial clusters, Discrete Math., 40 (1982), 203-217.
FORMULA
a(n) = A007175(n) - A182322(n) = (A007175(n) - A182299(n))/2 = A182322(n) - A182299(n).
a(n) = h(4,n) - H(4,n) in Table 8 of Hering link.
CROSSREFS
Cf. A007175 (oriented), A182322 (oriented), A182299 (achiral), A002293 (rooted), A371350 {3,3,oo}.
This is the half the difference of A007175 and A182299, both of which have Mathematica programs.
Sequence in context: A125373 A093145 A341917 * A037509 A037692 A126531
KEYWORD
nonn
AUTHOR
Robert A. Russell, Mar 20 2024
STATUS
approved