Howell Design

Let be a set of symbols, then a Howell design on symbol set is an array such that

1. Every cell of is either empty or contains an unordered pair of symbols from ,

2. Every symbol of occurs once in each row and column of , and

3. Every unordered pair of symbols occurs in at most one cell of .

References

Colbourn, C. J. and Dinitz, J. H. (Eds.) ``Howell Designs.'' Ch. 26 in CRC Handbook of Combinatorial Designs. Boca Raton, FL: CRC Press, pp. 381-385, 1996.

• de Bruijn Diagram
• de Bruijn Graph
• de Bruijn-Newman Constant
• de Bruijn Sequence
• de Bruijn's Theorem
• Debye Functions
• Debye's Asymptotic Representation
• Decagon
• Decagonal Number
• Decagram
• Decic Surface
• Decidable
• Decillion
• Decimal
• Decimal Expansion
• Decimal Period
• Decision Problem
• Decision Theory
• Decomposition
• Deconvolution
• Decreasing Function
• Decreasing Sequence
• Decreasing Series
• Dedekind Cut
• Dedekind Eta Function