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David Halitsky
  • Member for 4 years, 7 months
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6 votes
2 answers
222 views

Cases where ANY 2 of 3 +/- choices select one of four possible elements

4 votes
0 answers
117 views

Are the 240 roots of $E_8$ in ANY special relationship with any PARTICULAR set(s) of 1296 elements of $E_8$?

3 votes
1 answer
121 views

Does this linear representation of 112 roots of $E_8$ follow from the (extended) Hamming code's relation to the $E_8$ lattice?

3 votes
0 answers
158 views

"Why" do the 72 roots of the algebraic group E6 all have internal triplet structure?

2 votes
0 answers
51 views

Contexts for hexagonal numbers OTHER than "Vienna sausage" close-packing

2 votes
0 answers
213 views

Hyperboloids of one sheet, hyperbolic paraboloids, and Hilbert's famous "three skew lines"

2 votes
3 answers
131 views

What is the connection between these quantities?

1 vote
0 answers
116 views

Does the algebraic group E8 ever "collate" two sets of copies of the algebraic group E6?

1 vote
0 answers
43 views

If $E_6$ arises WITHIN $E_8$, does $E_8$ also arise FROM $E_6$?

1 vote
2 answers
83 views

Is the 9-space coordinatizion of the roots of $E_6$ "nicely" related to the 8-space coordinatization of these roots as 72 roots of $E_8$?

1 vote
1 answer
278 views

Two questions on three quadrics in $P^5$ whose intersection is a genus $5$ K3 surface.

1 vote
0 answers
50 views

$E_6$, $E_8$, and Coxeter's (anti-)prismatic projections of the n-dimensional cross-polytopes

1 vote
0 answers
48 views

Are the roots of E6 in 9-space ever treated as an orthogonal projection of a set of points in 11-space?

1 vote
0 answers
42 views

Cases of quasi-coincident "almost orthogonal" projections of n-dimenstional polytopes in (n-k)-spaces

1 vote
2 answers
72 views

Can formal language theory be correctly characterized as a branch of discrete mathematics?

1 vote
0 answers
74 views

Permutation of 0,,,n-1 as two vectors with n components or n vectors with 2 components

1 vote
0 answers
29 views

Does anyone know of any specific "eutactic hyperstars"?

1 vote
0 answers
79 views

Do the 240 roots of E8 implicitly define five disjoint copies of F4 (with 48 roots each)?

1 vote
0 answers
206 views

Is octonion structure related to the fact that an 8-cube has an equal number of 2-faces and 3-cells?

1 vote
1 answer
100 views

Sets of 72 elements with 3 subsets of 27, 27, and 18 elements

0 votes
0 answers
42 views

"N-free" permutations of (0,...,n-1) and pairs of orthogonal vectors in n-space

0 votes
0 answers
80 views

Are palindromic triples of roots of any interest in algebraic group E6?

0 votes
1 answer
88 views

I've posed this question re "quasi-dual" 1_22's offline to George Hart

0 votes
0 answers
67 views

Suppose it can be shown that any right(left)-regular finite-state grammar implicitly generates a "hypar"" surface

0 votes
1 answer
62 views

Cases of additive groups in which addition is "rightward elongation" and subtraction is "leftward elongation" of a left-to-right ordered string

0 votes
1 answer
283 views

Consider a set of 64 elements with subsets that have cardinalities 1, 1, 2, 5, 5, 10,10,10,20

0 votes
2 answers
161 views

Any Existing Time-Division Multiplexing Algorithm in which Slot-Allocation is Governed by the $E_8$ Root System?

0 votes
1 answer
69 views

Does any FORMAL theory of simplicity assert that "5+1+4+4 = 14" is "simpler" than "6+5+1+1+1 = 14" [closed]

0 votes
3 answers
85 views

What is the complete decomposition of $E_8$ roots in terms of the objects $A_0$, $A_1$, $A_2$, $B_0$, and $B_1$

0 votes
2 answers
136 views

Is this "co-location" of two $E_6$'s, two $F_4$'s, and one $E_8$ possible?