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A273089 Number of lattice n-gons with ordered sides 1, 2, 3, ..., n. 1
0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 5, 6, 0, 0, 584, 882, 0, 0, 18026, 194741, 0, 0, 644414, 960834, 0, 0, 229910636 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,8
COMMENTS
First 16 terms calculated by Stefan Kohl.
LINKS
Stefan Kohl, Lattice n-gons with ordered side lengths 1,2,3,…,n, Answer on MathOverflow, May 4, 2016.
L. Sallows, M. Gardner, R. K. Guy and D. E. Knuth, Serial isogons of 90 degrees, Math. Mag. 64 (1991), 315-324.
Wikipedia, Golygon
EXAMPLE
a(8) = 3:
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| . . . . . . | . | . . . | .\5 | | | . . | . ./.
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a(11) = 5:
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.\. . . . . . . . . . . . . . | . | . . . | \ . . . . . . . . |
. \ . . . . . . . . . . . . . | . | . . . | . .5. . . . . . . |
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. . . 10. . . . . . . . . . . | . | | . . . . . . . . . . . . .
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. - Hugo Pfoertner, Mar 20 2020
CROSSREFS
Cf. A007219.
Sequence in context: A316511 A317465 A051174 * A362021 A330735 A127773
KEYWORD
nonn,hard,more
AUTHOR
Bernardo Recamán, May 14 2016
EXTENSIONS
Typo in a(15) corrected and a(17)-a(27) added by Giovanni Resta, Mar 26 2020
STATUS
approved

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Last modified March 19 01:57 EDT 2024. Contains 370952 sequences. (Running on oeis4.)