Word Pronunciation & Dictionary

tetrahedral number

Word Rarity Very rare

Frequency: Zipf frequency 2.36 in modern English

Syllables: tetra-he-dral num-ber
IPA

25

Scrabble Score

17

Letters

4

Syllables

11

Unique Chars

Meaning

noun

A number which results from the summation of consecutive triangular numbers, starting from 1. If the triangular numbers in such a summation are depicted as horizontal triangular arrays of units then these arrays can be stacked vertically to yield a tetrahedral array.

Example Sentences

"The nᵗʰ tetrahedral number can be calculated with the formula #123;(n#43;1)³-(n#43;1)#92;over 6#125;."

Inflected Forms

tetrahedral numbers (plural)

Questions

What does tetrahedral number mean?: A number which results from the summation of consecutive triangular numbers, starting from 1. If the triangular numbers in such a summation are depicted as horizontal triangular arrays of units then these arrays can be stacked vertically to yield a tetrahedral array.

How to pronounce tetrahedral number

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