Definition:Balanced Incomplete Block Design

A Balanced Incomplete Block Design or BIBD with parameters $$v, b, r, k, \lambda$$ is a block design where:
 * $$v$$ is the number of points in the design.
 * $$b$$ is the number of blocks.
 * $$k$$ is the size of each block.
 * $$r$$ is the number of blocks any point can be in.
 * $$\lambda$$ is the number of times any two points can occur in the same block.