|
|
A226580
|
|
Smallest number of integer-sided squares needed to tile a 7 X n rectangle.
|
|
3
|
|
|
0, 7, 5, 5, 5, 5, 5, 1, 7, 6, 6, 6, 6, 6, 2, 8, 7, 7, 7, 7, 7, 3, 9, 8, 8, 8, 8, 8, 4, 10, 9, 9, 9, 9, 9, 5, 11, 10, 10, 10, 10, 10, 6, 12, 11, 11, 11, 11, 11, 7, 13, 12, 12, 12, 12, 12, 8, 14, 13, 13, 13, 13, 13, 9, 15, 14, 14, 14, 14, 14, 10, 16, 15, 15, 15
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
FORMULA
|
G.f.: x*(x^8-x^7-4*x^6-2*x+7)/(x^8-x^7-x+1).
a(n) = 1 + a(n-7) for n>8.
|
|
EXAMPLE
|
a(15) = 8:
._._._._._._._._._._._._._._._.
| | | |
| | | |
| | | |
| |_______|_______|
| | | | |
| | | |___|
|_____________|_____|_____|_|_|
|
|
MAPLE
|
a:= n-> `if`(n=1, 7, iquo(n, 7, 'r') +[0, 6, 5$5][r+1]):
seq(a(n), n=0..100);
|
|
MATHEMATICA
|
CoefficientList[Series[x*(x^8 - x^7 - 4*x^6 - 2*x + 7)/(x^8 - x^7 - x + 1), {x, 0, 100}], x] (* Wesley Ivan Hurt, Jan 15 2017 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn,easy
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|