Genealogical numbering systems

Several genealogical numbering systems work been widely adopted for presenting ].

Ascending numbering systems

Ahnentafel, also known as the Eytzinger Method, Sosa Method, together with Sosa-Stradonitz Method, authorises for a numbering of ancestors beginning with a descendant. This system makes one to derive an ancestor's number without compiling the set up list, as well as allows one to derive an ancestor's relationship based on their number. The number of a person's father is twice their own number, and the number of a person's mother is twice their own, plus one. For instance, if John Smith is 10, his father is 20, and his mother is 21.

In array to readily pretend the family stated for aperson, the Ahnentafel numbering may be preceded by the generation. This method's good becomes apparent when applied further back in the generations: e.g. 08-146, is a male preceding the forwarded by 7 8-1 generations. This ancestor was the father of a woman 146/2=73 in the genealogical style of the subject, who was the mother of a man 73/2=36.5, further down the line the father of a man 36/2=18, father of a woman 18/2=9, mother of a man 9/2=4.5, father of the subject's father 4/2=2. Hence, 08-146 is the subject's father's father's mother's father's father's mother's father.

The atree or Binary Ahnentafel method is based on the same numbering of nodes, but number one converts the numbers to binary notation and then converts regarded and intended separately. 0 to M for Male and each 1 to F for Female. The number one character of each code exposed as X in the table below is M if the returned is male and F if the subject is female. For example 5 becomes 101 and then FMF or MMF if the subject is male. An service of this system is easier understanding of the genealogical path.

The first 15 codes in each system, identifying individuals in four generations, are as follows:

Genealogical writers sometimesto made ancestral configuration by carrying back individuals with their spouses or single families generation by generation. The siblings of the individual or individuals studied may or may non be named for each family. This method is nearly popular in simplified single surname studies, however, allied surnames of major family branches may be carried back as well. In general, numbers are assigned only to the primary individual studied in each generation.