Not exactly a one-liner, but interesting in it own right as well. This is for a 64-bit integer perl - a 32-bit integer version needs a smaller table. 
#!/usr/bin/perl

use strict;
use warnings;

my @fib = (
                      0,
                      1,
                      1,
                      2,
                      3,
                      5,
                      8,
                     13,
                     21,
                     34,
                     55,
                     89,
                    144,
                    233,
                    377,
                    610,
                    987,
                   1597,
                   2584,
                   4181,
                   6765,
                  10946,
                  17711,
                  28657,
                  46368,
                  75025,
                 121393,
                 196418,
                 317811,
                 514229,
                 832040,
                1346269,
                2178309,
                3524578,
                5702887,
                9227465,
               14930352,
               24157817,
               39088169,
               63245986,
              102334155,
              165580141,
              267914296,
              433494437,
              701408733,
             1134903170,
             1836311903,
             2971215073,
             4807526976,
             7778742049,
            12586269025,
            20365011074,
            32951280099,
            53316291173,
            86267571272,
           139583862445,
           225851433717,
           365435296162,
           591286729879,
           956722026041,
          1548008755920,
          2504730781961,
          4052739537881,
          6557470319842,
         10610209857723,
         17167680177565,
         27777890035288,
         44945570212853,
         72723460248141,
        117669030460994,
        190392490709135,
        308061521170129,
        498454011879264,
        806515533049393,
       1304969544928657,
       2111485077978050,
       3416454622906707,
       5527939700884757,
       8944394323791464,
      14472334024676221,
      23416728348467685,
      37889062373143906,
      61305790721611591,
      99194853094755497,
     160500643816367088,
     259695496911122585,
     420196140727489673,
     679891637638612258,
    1100087778366101931,
    1779979416004714189,
    2880067194370816120,
    4660046610375530309,
    7540113804746346429,
);

sub fib {$fib[$_[0]]}   
         
__END__

[download]
No calculations needed.

In reply to Re^2: Fibonacci Numbers by Anonymous Monk
in thread Fibonacci Numbers by dReKurCe

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