[′lā·vē chē·vē′tä ‚sim·bəl] (mathematics) A symbol εi,j,…,swhere i, j, …, s are n indices, each running from 1 to n ; the symbol equals zero if any two indices are identical, and 1 or -1 otherwise, depending on whether i, j,…, s form an even or an odd permutation of 1, 2,…, n.