@ColinTheMathmo :DD You are a winner :sun: (yes, soroban and suanpan)

@dani could be 2**3 + sign, parity or carry

@dani Sorry, I don't know how to use an abacus. It might get a bit tricky to represent binary numbers like 101 or 010 within given physical space. Two-sided beads would be welcome.

About carry: Since I suggested a binary system, I thought of a manual version of digital half adders or manual division, etc.

@pschwede thank you for caring

ColinTheMathmo@ColinTheMathmo@mathstodon.xyz@dani It is more common for there to be 4 beads on the lower side. Then the upper bead represents 5, and each lower bead represents 1, so it can hold 0 through 9. Some abacuses will have 5 beads on the lower side, giving some redundancy and flexibility.

I've never seen an abacus with only three beads on the lower side.

It could be in base 8 ...