Ever wish there was a way to show your family relationships without having to draw the entire tree diagram? Well, there is and its called 'Ahnentafel'. This German word means 'ancestor chart'. It is not a chart in the normal sense, but is a list of your ancestors that shows the relationships numerically. Other genealogists can review the ancestry you are researching and can quickly see if their research matches or relates to yours in some way.
An ahnentafel is basically a numbered list where manipulation of a number leads to the ancestor of the person listed at the original number. Double a persons number and you find the father of that person. Double the number plus 1 gives the mother.
For example, you are the first name on the list, you are number 1. Your father is next; the second, number 2 (double your number). Your mother will be the third person, number 3 (double your number plus 1).
Extending this to your mother's parents: your grandfather on your mother's side (your mother's father) would be number 6 (your mother, 3, doubled is 6). Your grandmother on your mother's side would be number 7 (double 3 plus 1).
As you will see, the numbers can get quite high. For example, if you are number 1, your paternal great-great-great grandfather is 32 and his father is 64.
Now, lets look at it in chart form:
The use of collateral relationships can extend the ahnentafel considerably. Collateral relatives are those people who are not in your 'direct' line, but are the siblings of one of your ancestors; your father's brothers and/or sisters, for example (see line 4A above).
Collateral relatives are listed under their father with the father's number and a letter designation. The letter usually indicates the order of birth. For example, your father has a younger brother. This brother will be listed under your grandfather, Number 4 (remember your father is number 2, his father is double that, 4) as number 4B. If your father was the oldest, the A designation would not be used. His younger siblings would be listed as B, C, and so on. If your father was the second child, the B designation would not be used. Because your father is listed elsewhere in the chart, the letter indicating his position is not used.