Problem of the Month (September 2015)

This month we pack unit squares into small polyominoes. The problems of packing squares into squares, dominoes, and L-triominoes have been studied before. This month we pack squares into straight triominoes and the non-square tetrominoes. What is the smallest of these polyominoes that contains n non-overlapping unit squares?


ANSWERS

Solutions were received from Joe DeVincentis and Maurizio Morandi.

Straight Triomino
3.

s = 1
4.

s = 4/3 = 1.333+
5.

s = 5/3 = 1.666+
6.

s = 1.913+ (MM)
12.

s = 2
14.

s = 7/3 = 2.333+
15.

s = (9 + √2)/4 = 2.603+
16.

s = 8/3 = 2.666+
17.

s = 2.799+
18.

s = 2.876+ (JD)
19.

s = 2.930+
20.

s = 2.968+
27.

s = 3
30.

s = 10/3 = 3.333+
31.

s = 18/5 = 3.600
33.

s = 11/3 = 3.666+
34.

s = 3.772+ (JD)
35.

s = 3.827+ (JD)
36.

s = 3.850+ (JD)
37.

s = 3.900+ (JD)
38.

s = 3.924+ (JD)
39.

s = 3.972+ (JD)

T Tetromino
1.

s = 2√2/3 = .942+
4.

s = 1
5.

s = 4/3 = 1.333+
6.

s = 3/2 = 1.500
7.

s = 5/3 = 1.666+
8.

s = (4+5√2)/6 = 1.845+ (MM)
9.

s = 1.900+ (MM)
16.

s = 2
18.

s = 7/3 = 2.333+
19.

s = 2 + √2/3 = 2.471+
20.

s = 5/2 = 2.500
21.

s = (9 + √2)/4 = 2.603+
22.

s = 8/3 = 2.666+
23.

s = 14/5 = 2.800 (MM)
24.

s = (10 + √2)/4 = 2.853+
25.

s = 6(1 + √2)/5 = 2.897+ (MM)
26.

s = (12 + 2√2)/5 = 2.965+ (JD)
36.

s = 3
39.

s = 10/3 = 3.333+ (JD)
40.

s = 3.457+ (JD)
42.

s = 7/2 = 3.500 (JD)
43.

s = (13 + √2)/4 = 3.603+ (JD)
45.

s = 11/3 = 3.666+ (JD)
46.

s = 3.795+ (JD)
47.

s = 1 + 2√2 = 3.828+ (JD)
48.

s = 3.853+ (JD)
51.

s = 3.972+ (JD)

L Tetromino
4.

s = 1
5.

s = 4/3 = 1.333+
6.

s = 3/2 = 1.500
7.

s = 5/3 = 1.666+
8.

s = 1.858+
9.

s = 1.931+ (MM)
16.

s = 2
18.

s = 7/3 = 2.333+
19.

s = 2√3 – 1 = 2.464+ (MM)
20.

s = 5/2 = 2.500
21.

s = (9 + √2)/4 = 2.603+
22.

s = 8/3 = 2.666+
23.

s = 14/5 = 2.800 (MM)
24.

s = (10 + √2)/4 = 2.853+
25.

s = 2.878+ (JD)
26.

s = 2.934+ (JD)
36.

s = 3
39.

s = 10/3 = 3.333+ (JD)
40.

s = 3.447+ (JD)
42.

s = 7/2 = 3.500 (JD)
43.

s = (13 + √2)/4 = 3.603+ (JD)
45.

s = 11/3 = 3.666+ (JD)
46.

s = 3.786+ (JD)
47.

s = 3.824+ (JD)

S Tetromino
4.

s = 1
5.

s = 19/13 = 1.461+
7.

s = 3/2 = 1.500
8.

s = 4(4 + √3)/13 = 1.763+
9.

s = 1.931+ (MM)
10.

s = (5 + 2√2)/4 = 1.957+
16.

s = 2
17.

s = 1 + √2 = 2.414+
18.

s = 2.434+ (MM)
22.

s = 5/2 = 2.500
23.

s = 2.793+ (JD)
24.

s = (7 + √2)/3 = 2.804+
25.

s = 2.853+ (JD)
26.

s = 2.895+ (JD)
27.

s = 2.948+ (JD)
36.

s = 3
37.

s = 3 + √2/4 = 3.353+ (JD)
38.

s = 3.427+ (JD)
40.

s = 3.472+ (JD)
45.

s = 7/2 = 3.500 (JD)
47.

s = 3.767+ (JD)
48.

s = 3.871+ (JD)
49.

s = 3.941+ (JD)

I Tetromino
4.

s = 1
5.

s = 5/4 = 1.250
6.

s = 3/2 = 1.500
7.

s = 7/4 = 1.750
8.

s = 1.906+ (MM)
9.

s = (2 + 7√2)/6 = 1.983+ (MM)
16.

s = 2
18.

s = 9/4 = 2.250
19.

s = (11 + √2)/5 = 2.482+
20.

s = 5/2 = 2.500
21.

s = (12 + √2)/5 = 2.682+
22.

s = 11/4 = 2.750
23.

s = 2.807+
24.

s = 2.862+ (JD)
25.

s = 2.898+ (JD)
26.

s = 2.930+
27.

s = 2.985+ (JD)
36.

s = 3


If you can extend any of these results, please e-mail me. Click here to go back to Math Magic. Last updated 9/16/15.