Discussion on: Project Euler #2 - Even Fibonacci numbers

[Ross Henderson]

SQL

I have an answer, but I'm not 100% happy with it. It's not dynamic enough, but I need to do some more digging into Cycles it seems :)

with FIBONACCI (i, FIBO, PREV) as 
(
   select  
      1 i, 0 FIBO, cast(null as number) PREV 
   from 
      DUAL
   union all
   select 
      f1.i + 1  i, f1.FIBO + nvl(f1.PREV,1) FIBO, f1.FIBO PREV
   from 
      FIBONACCI f1
   where 
      f1.i < 35
)

select 
   sum(FIBO) as "Answer"
from 
   FIBONACCI
where 
   mod(FIBO, 2) = 0 
order by i;

-----------
Answer: 4613732