|
|
A083504
|
|
Triangle read by rows: for 1 <= k <= n, T(n, k) is the total perimeter of all squares contained in a square grid with n rows and k columns.
|
|
0
|
|
|
4, 8, 24, 12, 40, 80, 16, 56, 120, 200, 20, 72, 160, 280, 420, 24, 88, 200, 360, 560, 784, 28, 104, 240, 440, 700, 1008, 1344, 32, 120, 280, 520, 840, 1232, 1680, 2160, 36, 136, 320, 600, 980, 1456, 2016, 2640, 3300, 40, 152, 360, 680, 1120, 1680, 2352, 3120
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
T(n, n) = 4*A002415(n+1). Row sums are 4*A051836.
|
|
LINKS
|
Table of n, a(n) for n=1..53.
|
|
FORMULA
|
T(n, k) = (2k^3*n+6k^2*n+k^2+4k*n+2k-k^4-2k^3)/3.
|
|
EXAMPLE
|
T(3, 2) = 40 because the six 1 X 1 squares each have perimeter 4 and the two 2 X 2 squares each have perimeter 8.
|
|
CROSSREFS
|
Cf. A082652, A083003.
Sequence in context: A181688 A243557 A316687 * A277291 A254731 A291548
Adjacent sequences: A083501 A083502 A083503 * A083505 A083506 A083507
|
|
KEYWORD
|
nonn,tabl,easy
|
|
AUTHOR
|
Artemario Tadeu Medeiros da Silva (artemario(AT)uol.com.br), Jun 09 2003
|
|
EXTENSIONS
|
Edited by David Wasserman, Nov 18 2004
|
|
STATUS
|
approved
|
|
|
|