A019999 - OEIS

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A019999

Number of similarity classes of descendants created by bisection refinement from an initial n-simplex.

4, 36, 384, 4800, 69120, 1128960, 20643840, 418037760, 9289728000, 224811417600, 5885971660800, 165788201779200, 4999151930572800, 160687026339840000, 5484783832399872000, 198137815945445376000

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,1

REFERENCES

J. M. Maubach, The amount of similarity classes created by local n-simplicial bisection refinement, 1996.

J. M. Maubach, Local bisection refinement for n-simplicial grids generated by reflections, SIAM J. Scientific Computing, 16(1995), 210-227.

LINKS

Michael De Vlieger, Table of n, a(n) for n = 0..401

Ben Adenbaum, Jennifer Elder, Pamela E. Harris, and J. Carlos Martínez Mori, Boolean intervals in the weak Bruhat order of a finite Coxeter group, arXiv:2403.07989 [math.CO], 2024. See p. 11.

FORMULA

n*n!*2^(n-2).

MATHEMATICA

Array[#*#!*2^(# - 2) &[# + 1] &, 16] (* Michael De Vlieger, Mar 29 2024 *)

CROSSREFS

Sequence in context: A266093 A198638 A358954 * A291274 A239112 A002894

Adjacent sequences: A019996 A019997 A019998 * A020000 A020001 A020002

KEYWORD

nonn

AUTHOR

Joseph Maria Maubach (maubach(AT)una25.math.pitt.edu)

STATUS

approved