cibnacmei lujvo

x1 is a 3-dimensional vector with coordinates x2, x3 and x4.

Cf. nacmei, relnacmei.


In notes:

nacmei
x1 is a vector of dimension x2 with coordinates x3, x4, x5, ...
relnacmei
x1 is a 2-dimensional vector with coordinates x2 and x3.