In 1969, Word Ways published a trigram list by Faith and Ross Eckler; based on the 5th and 7th editions of Webster's Collegiate Dictionary, it gave the "most common" word for each trigram the authors could find. Since that time, Philip Cohen has greatly extended the list by mining Webster's Unabridged as well as various gazetteers and other references. For some letter-groups, such as ESS, a trigram is almost too trivial to be worth printing; but others, such as JVJ, are so hard that one would be pleased to find a word containing a bigram using two of these three letters. In this article, instead of picking a single length for each group of letters, I have tried to find the longest string for each possible choice of two different letters. Thus, the letter-pair ES can be used to generate the octagram aSSESSEES, and the letter-pair JV can be used to generate the bigram bliJVer.
"Long Digrammatic Strings,"
Word Ways: Vol. 15
, Article 4.
Available at: https://digitalcommons.butler.edu/wordways/vol15/iss2/4