Question

if 1,3,4 = 36, 2,1,3 = 27, 6,2,4 = 54, 4,3,7 = 63 then 5,1,9 = ?

Answer 1

Here is a longer list:

0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, 10946, 17711, 28657, 46368, 75025, 121393, 196418, 317811