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A013640 f-vector for 20-dimensional simplicial polytope providing counterexample to unimodality conjecture. 0
1, 4203045807626, 84060916163336, 798578704207074, 4791472253296106, 20363758019368323, 65164051780016980, 162910744316489788, 325834059588060117, 529707205213463823, 709935971390166248, 805494832051588614, 821976324224631043, 821976324224611712, 822000129478641948, 747383755288236256, 546761228419958342, 293715859557026466, 106920718330384544, 23458617733909980, 2345861773390998 (list; graph; refs; listen; history; text; internal format)
OFFSET

-1,2

COMMENTS

Fails unimodality conjecture because a(11) > a(12) < a(13). - Sean A. Irvine, Aug 17 2018

REFERENCES

G. M. Ziegler, Lect. on Polytopes, Springer 1995, p. 272.

LINKS

Table of n, a(n) for n=-1..19.

CROSSREFS

Sequence in context: A186912 A288284 A233504 * A185431 A139574 A233625

Adjacent sequences:  A013637 A013638 A013639 * A013641 A013642 A013643

KEYWORD

nonn,fini,full

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Ziegler reference added by Sean A. Irvine, Aug 17 2018

STATUS

approved

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Last modified December 15 17:03 EST 2019. Contains 330000 sequences. (Running on oeis4.)