Select polyominoes for a set (currently 1 or 2), for which tilings should be shown.
Then click "Show" button.
You may also see list of all polyomino sets for which data is available here.
Area: 4.
Perimeter: 8.
Size: 2x2.
Is rectangular: yes.
Is convex: yes.
Holes: 0.
Order: 1.
Square order: 1.
Odd order: 1.
Prime rectangles: ≥ 1.
Smallest rectangle and smallest square and smallest odd rectangle (2x2):
Blue number - strongly prime rectangle (which cannot be divided into two or more number of rectangles tileable by this set).
Green number - weakly prime rectangle (which cannot be divided into two rectangles tileable by this set, but which can be divided into three or more rectangles).
Purple number - prime rectangle (unknown if weakly or strongly prime).
Red number - composite rectangle (which can be divided into two rectangles tileable by this set).
Gray number - it is unknown whether rectangle is prime or composite.
Question mark (?) - solution count is unknown.
Click on underlined numbers to view picture with one solution.
Smallest prime reptile (4Ox2):
Smallest torus and smallest square torus and smallest odd torus (2x2):
Smallest Baiocchi figure (area 4):
$N(w; h)$ - number of ways to tile $w\times h$ rectangle (including symmetric solutions)
$T(w; h) = \begin{cases} 1, & N(w; h) \geq 1 \\ 0, & \text{else} \end{cases}$ - tileability function, $1$ if tiles rectangle, $0$ otherwise
$A(w; h) = \left(N(w; h)\right)^{\frac{1}{wh}}$ - average number of ways to tile cell in $w\times h$ rectangle (including symmetric solutions)
$G(T; x; y) = \sum_{w=1}^{\infty}\sum _{h=1}^{\infty}T(w; h)x^wy^h$ - bivariate generating function of $T(w; h)$
$G(A; x; y) = \sum_{w=1}^{\infty}\sum _{h=1}^{\infty}A(w; h)x^wy^h$ - bivariate generating function of $A(w; h)$
$N(n; 2m + 1) = T(n; 2m + 1) = 0 \tag{1}$
$N(2n; 2m) = T(2n; 2m) = A(2n; 2m) = 1 \tag{2}$
$N(w; h) = T(w; h) = A(w; h) = \frac{1}{4} \left(1+(-1)^w\right) \left(1+(-1)^h\right) \tag{3}$
$G(T; x; y) = G(A; x; y) = \frac{x^2 y^2}{\left(1-x^2\right)\left(1-y^2\right)} \tag{4}$
