What was Fibonacci's rabbit problem called?

Answer 1

"In Fibonacci's Liber Abaci book, chapter 12, he introduces the following problem (here in Sigler's translation - see below): How Many Pairs of Rabbits Are Created by One Pair in One Year

A certain man had one pair of rabbits together in a certain enclosed place, and one wishes to know how many are created from the pair in one year when it is the nature of them in a single month to bear another pair, and in the second month those born to bear also.

He then goes on to solve and explain the solution: Because the above written pair in the first month bore, you will double it; there will be two pairs in one month.

One of these, namely the first, bears in the second montth, and thus there are in the second month 3 pairs;

of these in one month two are pregnant and in the third month 2 pairs of rabbits are born, and thus there are 5 pairs in the month;

...

there will be 144 pairs in this [the tenth] month;

to these are added again the 89 pairs that are born in the eleventh month; there will be 233 pairs in this month.

To these are still added the 144 pairs that are born in the last month; there will be 377 pairs, and this many pairs are produced from the abovewritten pair in the mentioned place at the end of the one year.

You can indeed see in the margin how we operated, namely that we added the first number to the second, namely the 1 to the 2, and the second to the third, and the third to the fourth and the fourth to the fifth, and thus one after another until we added the tenth to the eleventh, namely the 144 to the 233, and we had the abovewritten sum of rabbits, namely 377, and thus you can in order find it for an unending number of months. "

- excerpt from http://www.maths.surrey.ac.uk/hosted-sites/R.Knott/Fibonacci/fibBio.html