Is there a name for such defined numbers?

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I've have defined below new set of like-complex numbers (will be called $\Bbb{HC}$ here as my proposition for name for them is hexagonal-complex):

Let $z = (u,d) \in \mathbb{HC}$ where $u,d \in \mathbb{R}$ such that:

  • $(1,0)(1,0) \triangleq (0,-1)$
  • $(0,1)(0,1) \triangleq (-1,0)$
  • $(0,1)(1,0) \triangleq (1,0)(0,1) \triangleq (0,1)+(1,0)$
  • $\mathbb{HC}$ is a 2d vector space over $\mathbb{R}$

Such defined numbers have following properties, which you can check for yourself:

  • $z_1 z_2 = z_2 z_1$
  • $z_1(z_2+z_3) = z_1 z_2+z_1 z_3$
  • $(1,1)z_1 = z_1$

If we define

  • $z^* = (u,d)^* \triangleq (d,u)$
  • $|z| \triangleq \sqrt{zz^*}$

Than one can easly proove that: $|z_1 z_2| = |z_1| |z_2|$

My name hexagonal-complex is from the fact that you can do an identification to complex numbers as:

$(1,0) \leftrightarrow e^{i \pi /3}$

$(0,1) \leftrightarrow e^{-i \pi /3}$

And the lattice of points $(u,d)$ where $u,d \in \mathbb{Z}$ is a hexagonal latice in complex plane.

And finally the question is: do such defined numbers have a name other than what I called them?

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$\Bbb{HC}$ does not define a hexagonal lattice in the complex plane; $(1,1)$ is mapped to 1 using your $e^{i\pi/3}$ and $e^{-i\pi/3}$ mappings, which would lie in the centre of one of the hexagons you perceive. Indeed, it's easy to see that a triangular lattice is formed instead, and your set of integral points in $\Bbb{HC}$ are the Eisenstein integers.

Since $\Bbb{HC}$ is a 2-dimensional vector space like $\Bbb C$, it is merely $\Bbb C$ with a linear transformation, not anything new.