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A127709 Triangle T(n, d) = the number of isomorphism classes of smooth Fano d-polytopes with n vertices, read by rows (n >= 2, 1 <= d < n). 1
1, 0, 1, 0, 2, 1, 0, 1, 4, 1, 0, 1, 7, 9, 1, 0, 0, 4, 28, 15, 1, 0, 0, 2, 47, 91, 26, 1, 0, 0, 0, 27, 268, 257, 40, 1, 0, 0, 0, 10, 312, 1318, 643, 62, 1, 0, 0, 0, 1, 137, 2807, 5347, 1511, 91, 1, 0, 0, 0, 1, 35, 2204, 19516, 19453, 3331 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
2,5
LINKS
Mikkel Obro, An algorithm for the classification of smooth Fano polytopes, arXiv:0704.0049 [math.CO], Apr 02 2007, p. 15.
Mikkel Øbro, Classification of smooth Fano polytopes, PhD thesis, 2007. See Appendix A.
EXAMPLE
Table begins:
n |d=1|d=2|d=3|d=4|d=5|d=6|d=7
1 |
2 | 1 |
3 | | 1 |
4 | | 2 | 1 |
5 | | 1 | 4 | 1 |
6 | | 1 | 7 | 9 | 1 |
7 | | | 4 | 28| 15| 1 |
8 | | | 2 | 47| 91| 26| 1
9 | | | | 27|268|257| 40
CROSSREFS
Column sums are A140296.
Sequence in context: A116088 A136501 A180983 * A343730 A343761 A336423
KEYWORD
nonn,tabl
AUTHOR
Jonathan Vos Post, Apr 03 2007
EXTENSIONS
Edited and leading zeroes in rows and few more values added by Andrey Zabolotskiy, Sep 19 2018
STATUS
approved

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Last modified June 1 11:52 EDT 2023. Contains 363068 sequences. (Running on oeis4.)