| 释义 |
triangulo-|traɪˈæŋgjʊləʊ|
used as combining form of L. triangulum triangle, in triangulo-pyramidal, triangulo-triangular adjs., applied to certain series of figurate numbers: see quots., and cf. pyramidal 4, triangular 2 b.
[1646F. Vieta Opera 294 In prima adfectione per unitatis crementum, in secunda per numeros triangulos, in tertia per numeros pyramidales, in quarta per numeros triangulo-triangulos, in quinta per numeros triangulo-pyramidales.] 1715Phil. Trans. XXIX. 183 A series of Fractions..whose Numerator is a given Number and Denominators are triangular or pyramidal or triangulo-triangular Numbers, &c. 1785Hutton Math. Tables 7 The several orders of figurate numbers, which he [Vieta] calls triangular, pyramidal, triangulo-triangular, triangulo-pyramidal. |