# math

posted by
**zgord**
.

*if it is in parentheses, it is subscripted.

the sequence {a(n)} is defined recursively by a(1) = 1, a(2) = 1 and for all n>= 1, a(n+2) = a(n+1) + a(n). use the principle of mathematical induction to prove that a(1) + a(2) + a(3) + ... + a(n) = a(n+2) - 1