© 1980 by British Computer Society
The size of arrays for a prime implicant generating algorithm
Department of Computer Science, University of Gunma, Kiryu-City, Gunma-Prefecture, Japan
A number of interesting combinatorial problems have arisen by investigating a computer implementation of a prime implicant generator called the star-algorithm. These problems have been motivated by the necessity of estimating suitable sizes of arrays to store intermediate results when the algorithm is written in a computer language such as ALGOL 60. Bn(r) denotes the set of r-cubes of the n-variable Boolean algebra and
denotes the star-product. P(Bn(r))=#({b|b
Bn(r) and a
b
&}), where #(S) is the number of elements of set S, a is an arbitrary element of Bn(r), and a
b
& means that the star-product of a and b is a cube. The main combinatorial result in this paper is that for all 0<
, K1(n33/4)n
max{P(Bn(r))|0
r
n}
k2(33/4 +
)n. where k1 and k2 are constants independent of n.
Received June 1978.
* Now at Department of Computer Science, University of Gunma, Kiryu-city, Gunma-prefecture, Japan.
Computer Science Division, Department of Mathematics, The City University, London EC1V 4PB