gistfile1.fs

> let rec fib (start,step,list) =
  if (start > 4000001) then (1,start, start::list)
  else fib (start+step, start, (start::list))

val fib : int * int * int list -> int * int * int list

> let start,max,list = fib (1,1,[])


val start : int = 1
val max : int = 5702887
val list : int list =
  [5702887; 3524578; 2178309; 1346269; 832040; 514229; 317811; 196418; 121393;
   75025; 46368; 28657; 17711; 10946; 6765; 4181; 2584; 1597; 987; 610; 377;
   233; 144; 89; 55; 34; 21; 13; 8; 5; 3; 2; 1]

> list
|> List.filter (fun n->n%2=0)
|> List.fold (+) 0

val it : int = 4613732