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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. MathOverflow, Lattice n-gons with ordered side lengths 1,2,3,...,n Giovanni Resta, Examples of n-gons with minimal and maximal area 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:   . . . . . ._._._.   . . . . . . . .    ._._._._._._._.   . . . . . | . . |   . . . . . . . .    | . . . . . . |   . . . . . | . ._|   ._._._._._._._.    | . . . . . . |   . . . . . | . | .   | . . . . . . |    | . . . . . . |   ._._._._._| . | .   | . . .   . . |    | . . . . . . |   | . . . . . . | .   | . . . |\. . |    | . . . . . . |   | . . . . . . | .   | . . . | \ . |    | ._._._. . . |   | . . . . . . | .   | . . . | .\5 |    | | . . | . ./.   | . . . . . . | .   | ._._._| . .\|    |_| . . | ./5 .   | . . . . . . | .   | | . . . . . .    . . . . | / . .   |_._._._._._._| .   |_| . . . . . .    . . . . |/. . . . a(11) = 5:   . . . . . . . . . . . ._._._._._._._._._. . . . . . . .   . . . . . . . . . . . .\. . . . . . . . | . . . . . . .   . . . . . . . . . . . . . \ . . . . . . | . . . . . . .   . . . . . . . ._._._. . . . .\. . . . . | . . . . . . .   . . . . . . . | . . | . . . . .10 . . . | . . . . . . .   . . . . . . ._| . . | . . . . . . \ . . | . . . . . . .   . . . . . . | . . . | . . . . . . . .\. | . . . . . . .   . . . . . . | . . . | . . . . . . . . | | . . . . . . .   . . . . . . | . . . . \ . . . . . . . | |_._._._._._._.   |\. . . . . | . . . . . 5 \ . . . . . | . . . . . . . |   | \ . . . . | . ._._._._._._. . . . . | . . . . . . . |   | .\. . . . | . | . . . . . . . . . . | . . . . . . . |   | . .\. . . | . | . . . . . . . . . . | . . . | \ . . |   | . . 10. . | . | . . . . . . . . . . | . . . | . 5 . |   | . . . \ . | . | . . . . . . . . . . | . . . | . . \ |   | . . . . \ | . | . . . . . . . . . . | ._._._| . . . .   | . . . . .\| . | . . . . . . . . . . | | . . . . . . .   |_._._._._._._._| . . . . . . . . . . |_| . . . . . . . .   . ._._._. . . . . . . . . . . . . . . . . . . . . . . . . . . .   . | . . | . . . . . . . . . . . . . . . . . ./| . . . . . . . .   ._| . . | . . . . . . . . . . . . . . . . ./. | . . . . . . . .   | . . . | . . . . . . . . . . . . . . . . / . | . . . . . . . .   | . . . | . . . . . . . . . . . . . . . ./. . | . . . . . . . .   | . . . .\. . . . . . . . . . . . . . .10 . . | . . . . . . . .   | . . . . . 5 . . . . . . . . . . . . / . . . | . . . . . . . .   | . . . . . . .\. . . . . . . . . . / . . . . | . . . . . . . .   | . . . . . . . | . . . . . . . . ./. . . . . | . . . . . . . .   | . . . . . . . | . . . . . . . . | . . . . . |_._._._._._._._.   | . . . . . . . | . . . . . . . . | . . . . . . . . . . . . . |   | . . . . . . . | . . . . . . . . | . . . . . . . . . . . . . |   | . . . . . . . | . . . . . . . . | . . . . . . . . . . . . . |   | . . . . . . . |_._._._._._._. . | . . . . . . . . . . . . . |   .\. . . . . . . . . . . . . . | . | . . . | \ . . . . . . . . |   . \ . . . . . . . . . . . . . | . | . . . | . .5. . . . . . . |   . . \ . . . . . . . . . . . . | . | . . . | . . .\._._._._._._|   . . . \ . . . . . . . . . . . | . | ._._._| . . . . . . . . . .   . . . 10. . . . . . . . . . . | . | | . . . . . . . . . . . . .   . . . . \ . . . . . . . . . . | . |_| . . . . . . . . . . . . .   . . . . . \ . . . . . . . . . |   . . . . . .\._._._._._._._._._| .   . . . . . . . . . . . . . . . .   |\. . . . . . . . . . . . . . .   | .\. . . . . . . . . . . . . .   | . \ . . . . . . . . . . . . .   | . . \ . . . . . . . . . . . .   | . . 10. . . . . . . . . . . .   | . . . .\. . . . . . . . . . .   | . . . . \ . . . . . . . . . .   | . . . . . \_._._._._._._._._.   | ._._._. . . . . . . . . . . |   | | . . | . . . . . . . . . . |   |_| . . | . . ./| . . . . . . |   . . . . | . 5 . | . . . . . . |   . . . . |/. . . | . . . . . . |   . . . . . . . . | . . . . . . |   . . . . . . . . | . . . . . . |   . . . . . . . . |_._._._._._._| . - Hugo Pfoertner, Mar 20 2020 CROSSREFS Cf. A007219. Sequence in context: A316511 A317465 A051174 * A330735 A127773 A194498 Adjacent sequences:  A273086 A273087 A273088 * A273090 A273091 A273092 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 January 27 13:45 EST 2022. Contains 350607 sequences. (Running on oeis4.)