oblong number

English

Noun

oblong number (plural oblong numbers)

1. (mathematics) rectangular number
   • 1952 [c. 100], Nicomachus of Gerasa, translated by Martin Luther D’Ooge, edited by Robert Maynard Hutchins, Mortimer J. Adler, and Wallace Brockway, Introduction to Arithmetic II (Great Books Of The Western World; 11), William Benton (Encyclopædia Britannica, Inc.), page 838:

     If, however, the sides differ otherwise than by 1, for instance, by 2, 3, 4 or succeeding numbers, as in 2 times 4, 3 times 6, 4 times 8, or however else they may differ, then no longer will such a number be properly called a heteromecic, but an oblong number. For the ancients of the school of Pythagoras and his successors saw “the other”³ and “otherness” primarily in 2, and “the same” and “sameness” in 1, as the two beginnings of all things, and these two are found to differ from each other only by 1. Thus “the other” is fundamentally “other” by 1, and by no other number, and for this reason customarily “other” is used, among those two speak correctly, of two things and not of more than two.