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A141682
Number of isomorphism classes of (2n+1)-reflexive polygons.
1
16, 1, 12, 29, 1, 61, 81, 1, 113, 131, 2, 163, 50, 2, 215, 233, 2, 34, 285, 3, 317, 335, 2, 367, 182, 3, 419, 72, 4, 469, 489, 3, 93, 539, 4, 571, 591, 3, 185, 641, 5, 673, 131, 5, 725, 240, 6, 148, 795, 5, 827, 845, 3, 877, 897, 7, 929, 186, 6, 338, 656, 7, 240, 1049, 8, 1081, 393, 5, 1133, 1151, 8, 542, 245, 7, 1235, 1253
OFFSET
0,1
COMMENTS
There are no l-reflexive polygons for even index l.
LINKS
Andrey Zabolotskiy, Table of n, a(n) for n = 0..99 (from the Graded Ring Database)
Dimitrios I. Dais, On the Twelve-Point Theorem for l-Reflexive Polygons, arXiv:1806.08351 [math.CO], 2018.
A. M. Kasprzyk and B. Nill, Reflexive polytopes of higher index and the number 12, arXiv:1107.4945 [math.AG], 2011.
A. M. Kasprzyk and B. Nill, Toric l-reflexive surfaces at Graded Ring Database.
FORMULA
It seems that for n > 2, a(n) = 17*n - k where k = 21, 22, 23, 24 iff 2*n+1 is a prime from A068228, A068229, A040117, A068231, respectively. - Andrey Zabolotskiy, Apr 21 2022
EXAMPLE
a(0)=16 equals the number of isomorphism classes of (1-)reflexive polygons, A090045(2).
CROSSREFS
Cf. A090045.
Sequence in context: A321673 A040269 A360028 * A040270 A303327 A070539
KEYWORD
nonn
AUTHOR
Benjamin Nill, Jul 02 2012
STATUS
approved