[go: up one dir, main page]
More Web Proxy on the site http://driver.im/
login
Revision History for A363381 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing entries 1-10 | older changes
a(n) is the number of distinct n-cell patterns that tile an n X n square.
(history; published version)
#79 by Alois P. Heinz at Thu Jul 06 09:35:58 EDT 2023
STATUS

proposed

approved

#78 by Jon E. Schoenfield at Mon Jun 12 23:50:12 EDT 2023
STATUS

editing

proposed

Discussion
Tue Jun 13
02:29
Thomas Young: looks good!  Thanks!
Wed Jun 21
01:20
Thomas Young: What do I need to do to get this published?
#77 by Jon E. Schoenfield at Mon Jun 12 23:50:00 EDT 2023
COMMENTS

Composite number For composite numbers n, an n X n squares square will always have at least two n-cell patterns. This is due to the fact that composite numbers have at least 2 factor pairs: a 1, f1f2, X n pattern and an f1, X f2. ( pattern, where 1 < f1 and <= f2 are not necessarily distinct < n and f1f2 f1*f2 = n.) n-cell patterns For example, a 14 X 14 square can be made that tessellate the tiled using fourteen 1 X 14 rectangles or fourteen 2 X 7 rectangles; a 15 X 15 square by creating n can be tiled using fifteen 1 X 15 rectangles that are 1 or fifteen 3 X f1f2. Or, the n 5 rectangles; a 9 X n 9 square can be tessellated tiled using n nine 1 X 9 rectangles that are f1 or nine 3 X f23 squares (as in Sudoku!).

For example, for prime numbers p, a 14 p X 14 p square, its factor pairs are 1,14 and 2,7. It can always be tiled using fourteen 1 X 14 tessellated with p rectangles or fourteen 2 that are 1 X 7 rectanglesp.

For a 15 X 15 square, its factor pairs are 1,15 and 3,5. It can be tiled using fifteen 1 X 15 rectangles or fifteen 3 X 5 rectangles.

For a 9 x 9 square, its factor pairs are 1,9 and 3,3. It can be tiled using nine 1 X 9 rectangles or nine 3 X 3 squares (Sudoku!).

Prime number p X p squares can always be tessellated with p rectangles that are 1 X p.

STATUS

proposed

editing

Discussion
Mon Jun 12
23:50
Jon E. Schoenfield: How about this? I tried to make it more concise.
#76 by Thomas Young at Mon Jun 12 21:41:59 EDT 2023
STATUS

editing

proposed

Discussion
Mon Jun 12
21:56
Thomas Young: and I still think 62714 is suspect.  However, my programming skills are not sufficient to prove it incorrect.
#75 by Thomas Young at Mon Jun 12 21:41:36 EDT 2023
COMMENTS

Composite number n X n squares will always have at least two n-cell patterns. This is due to the fact that composite numbers have at least four factors 2 factor pairs: 1, f1f2, and f1, f2. (f1, and f2, are not necessarily distinct and f1f2 = n. ) n-cell patterns can be made that tessellate the square by creating n rectangles that are 1 X f1f2. Or, the n X n square can be tessellated using n rectangles that are f1 X f2.

For example, for a 14 X 14 square, its factor pairs are 1,14 and 2,7. It can be tiled using fourteen 1 X 14 rectangles or fourteen 2 X 7 rectangles.

For a 15 X 15 square, its factor pairs are 1,15 and 3,5. It can be tiled using fifteen 1 X 15 rectangles or fifteen 3 X 5 rectangles.

For a 9 x 9 square, its factor pairs are 1,9 and 3,3. It can be tiled using nine 1 X 9 rectangles or nine 3 X 3 squares (Sudoku!).

STATUS

proposed

editing

Discussion
Mon Jun 12
21:41
Thomas Young: closer?
#74 by Thomas Young at Mon Jun 12 21:11:51 EDT 2023
STATUS

editing

proposed

Discussion
Mon Jun 12
21:26
Jon E. Schoenfield: I think that's at least a step in the right direction. :-)  I.e., it's not about primes necessarily, but about factors other than 1 and n. However, for a number like, say, 15, I think it's better to refer to 1, 3, 5, and 15 as "divisors", rather than "factors", of 15.  Also, "composite numbers have at least four factors 1, f1, f2, and f1f2" may seem to some readers to imply that f1 and f2 are necessarily different ... but what if n is the square of a prime?
#73 by Thomas Young at Mon Jun 12 21:11:37 EDT 2023
COMMENTS

Composite number n X n squares will always have at least two n-cell patterns. This is due to the fact that composite numbers have at least two prime four factors p1 1, f1, f2, and p2f1f2. n-cell patterns can be made that tessellate the square by creating n rectangles that are 1 X p1p2f1f2. Or, the n X n square can be tessellated using n rectangles that are p1 f1 X p2f2.

STATUS

proposed

editing

Discussion
Mon Jun 12
21:11
Thomas Young: better?
#72 by Jon E. Schoenfield at Mon Jun 12 21:01:52 EDT 2023
STATUS

editing

proposed

#71 by Jon E. Schoenfield at Mon Jun 12 20:59:36 EDT 2023
COMMENTS

Composite number n X n squares will always have at least two n-cell patterns. This is due to the fact that composite numbers have at least two prime factors p1 and p2. Nn-cell patterns can be made that tessellate the square by creating n rectangles that are 1 X p1p2. Or, the n X n square can be tessellated using n rectangles that are p1 X p2.

Prime number pXp p X p squares can always be tessellated with p rectangles that are 1 X p.

STATUS

proposed

editing

Discussion
Mon Jun 12
21:01
Jon E. Schoenfield: Hmmm ... I'm not sure about the wording in the paragraph "Composite number n X n squares will always have at least two n-cell patterns. This is due to the fact that composite numbers have at least two prime factors p1 and p2. n-cell patterns can be made that tessellate the square by creating n rectangles that are 1 X p1p2.  Or, the n X n square can be tessellated using n rectangles that are p1 X p2." What if n = 30?
#70 by Thomas Young at Mon Jun 12 20:32:11 EDT 2023
STATUS

editing

proposed