Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options answers only not deleted user 3402

Design theory is the subfield of combinatorics concerning the existence and construction of highly symmetric arrangements. Finite projective planes, latin squares, and Steiner triple systems are examples of designs.

6 votes

Status of Hadamard matrix conjecture

With all due respect to Colin McLarty, here is (in my not so humble opinion) a better answer. The conjecture (For every positive integer $k,$ there is a square matrix $H$ of order $4k$ such that $H$ …
kodlu's user avatar
  • 10.4k
1 vote

Minimum covers of complete graphs by $4$-cycles

If n is even, you can form a partial edge cover with disjoint four-cycles: pick points u and v, and cover all edges coming from u and from v (except for uv) by disjoint cycles. Now recurse, leaving n/ …
Gerhard Paseman's user avatar
3 votes

Maximum determinant of $\{0,1\}$-valued $n\times n$-matrices

( I assume the R in the title is the real numbers. For arbitrary rings R an order needs to be specified before remarks like those below should be made. ) Using the method suggested by Robin Chapman, …
Gerhard Paseman's user avatar