"Fibonacci Sequence III"

Given the first few Fibonacci numbers:

1 1 2 3 5 8 13 ...

What is the sum of the first 75 Fibonacci numbers?

As an example above, the sum of the first 7 numbers is 33.

Well this challenge was simple... simply modify the loop from challenge 13, and add a counter that gets added to each time.

Awnser:

Source:

function solution(){
   $result = 2;
   $prevno = 1; // no 1
   $currno = 1; // no 2
   for( $i = 1; $i <= 73; $i++ ){
      $placeholder = bcadd($prevno, $currno);
      $prevno = $currno;
      $currno = $placeholder;
      $result = bcadd($result, $currno);
   }
   echo "".$result."";
}