s=' '.ord;a=s%b=s/s
b.upto(s-b-b){|x|p "#{x} #{a=b+b=a}"}

Cut down another 4 characters due to requirement dropping :
space ascii code is 32, b = 32/32 => 1 and that modulo 1 is zero. 
It's just question of iterating through after that.

30 Fibonacci Numbers Without Using Numbers In Ruby(58)

Ruby