WOLFRAM|DEMONSTRATIONS PROJECT

Fibonacci Rabbits

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generations
4
show
labels
rabbits
nm[m[m,n],n[m]],Textgenerations,{-2,3.10473},Textnumber of pairs,{3.77413,3.10473},{Text[1,{-2,2.6612}],Text[2,{-2,1.77413}],Text[3,{-2,0.887066}],Text[4,{-2,0.}]},{Text[1,{3.77413,2.6612}],Text[1,{3.77413,1.77413}],Text[2,{3.77413,0.887066}],Text[3,{3.77413,0.}]}
a pair of rabbits:born|mature|survive
In 1202 Fibonacci investigated how fast rabbits could breed.
Suppose a pair of rabbits, one male and one female, start a family. Rabbits mature at the age of one month (labeled "m") and a female produces a new pair of rabbits (labeled "n") at the end of its second month.
Suppose that the rabbits survive forever and that a female always produces one new pair (one male, one female) every month, giving the original pair and a new one.
How many pairs will there be in eight generations?