Fórmula para cálculo de parentesco

Um, there isn't one?

There are various tools for figuring out "nth cousin m times removed", but there aren't really any formulas involved, only diagrams (sometimes). I find it easiest to just chart it out myself, though.

For example, I recently found my father's second cousin, and sent him a version of the following chart:

                      Paulovkin Mária

                             |

                  ----------------------

(half-)           |                    |

siblings   Paulovkin Zsuzsanna    Pohánka Mária

                  |                    |

cousins     Selmeczy Erzsébet     Makovínyi Pál

                  |                    |

2nd cousins   Palotay Csaba       [new cousin]

                  |

                 [me]

(All names are of deceased people.)

In English, our relationship is "second cousins once removed", but I was writing in Hungarian, which doesn't use the "removed" formulation, so I phrased it as "my father's second cousin". If you're using a language that does use an equivalent of "removed" for generational differences, then the degree of cousinship is counted to the person who is closer to the common ancestor(s), and the number of generations needed to get to the other person is the number of times removed.

Since in English further ancestors just get another "great" tacked on, there are people who use "formulas" based on the number of greats to figure out degree of cousinship, but I find it too easy to get confused between the different numberings (one for the number of greats, another in the opposite direction for the degree of cousinship, and a third for the generational offset). Plus, in Hungarian, everyone past your 3ggp is just your ancestor; there aren't any more words for it.