Numerically Identifying blood relations

This convention I developed uniquely identifies blood relatives showing the number of generations one has to go "up" the tree to reach a common ancestor, then "down" to reach the distant relative. The format is N,M and the following table shows assignments for the most common relatives:

• 0,0  — Me
• 1,0  — Parents
• 2,0  — Grandparents
• 3,0  — Great Grandparents (1ggp)
• 4,0  — 2nd Great Grandparents (2ggp)
• 1,1  — Siblings
• 1,2  — Nieces and Nephews
• 1,3  — Grand Nieces and Nephews
• 2,1  — Aunts and Uncles
• 2,2  — First Cousins
• 2,3  — First Cousins Once Removed (1x1)
• 2,4  — First Cousins Twice Removed (1x2)
• 3,1  — Grand Aunts and Uncles
• 3,2  — First Cousins Once Removed (1x1)
• 3,3  — Second Cousins
• 4,1  — Great-Grand Aunts and Uncles
• 0,1  — Sons and Daughters
• 0,2  — Grandchildren
• 0,3  — Great Grandchildren

Notice that if you reverse the numbers, you find the corresponding relation from that relative to you (e.g., 2,1 for uncle, but 1,2 for nephew). Another interesting feature is that this format disambiguates between "your first cousin once removed" who is the child of your first cousin, from "your first cousin once removed" who is your parent's cousin.

SO - how do you go from that to a text relationship?

For the close-in relatives you have to pretty much memorize it.  Further out, it actually gets easier.

• X,0 = (X-2) great grandparent, e.g., 7,0 = 5th great-grandparent.   Conversely, 0,X is (X-2) great grandchild.
  
• X,1 = (for X > 3)  (X-3) grand uncle/aunt
  
• X,X = (X-1)th cousin, e.g., 9,9 is 8th cousin
• All the other X,Y's that are not one of specially-named relations are some cousin with some degree of removal.   ALL of them work like this:
• Let's use 7,5
• Take the smaller number and subtract one: that's the degree of cousin (so 4th)
• Subtract the two numbers - that's the degrees of removal (so here, 2)
• 7,5 = 4th cousin 2x removed.
• 5,7 is ALSO 4th cousin 2x removed.