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A330659
The number of free polyiamonds with n cells on an order-7 triangular tiling of the hyperbolic plane.
3
1, 1, 1, 1, 3, 4, 12, 27, 78, 208, 637, 1870, 5797, 17866, 56237, 177573, 566904, 1818527, 5874180, 19065038
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OFFSET
0,5
COMMENTS
This gives the number of polyforms with n cells in the hyperbolic tiling with Schläfli symbol {3,7}.
This sequence is computed from via program by Christian Sievers in the Code Golf Stack Exchange link.
LINKS
Table of n, a(n) for n=0..19.
Code Golf Stack Exchange, Impress Donald Knuth by counting polyominoes on the hyperbolic plane
Wikipedia, Order-7 triangular tiling
Wikipedia, Polyiamond
PROG
Several working programs are available via the Code Golf link.
CROSSREFS
Analogs with different Schläfli symbols are A000207 ({3,oo}), A000577 ({3,6}), A005036 ({4,oo}), and A119611 ({4,5}).
Sequence in context: A000942 A255436 A197459 * A000207 A002986 A147569
Adjacent sequences: A330656 A330657 A330658 * A330660 A330661 A330662
KEYWORD
nonn,more
AUTHOR
Peter Kagey, Mar 01 2020
EXTENSIONS
a(11)-a(19) from Ed Wynn, Feb 14 2021
STATUS
approved

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Last modified November 14 21:21 EST 2024. Contains 377732 sequences.
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