Fibonacci function or sequence
Brainfuck, 22 strokes
+>++[-<<[->+>+<<]>>>+]
Generates the Fibonacci sequence gradually moving across the memory tape.
Haskell, 17 15 14 chars
f=1:scanl(+)1f
Try it online!
Perl 6, 10 chars:
Anonymous infinite fibonacci sequence list:
^2,*+*...*
Same as:
0, 1, -> $x, $y { $x + $y } ... Inf;
So, you can assign it to an array:
my @short-fibs = ^2, * + * ... *;
or
my @fibs = 0, 1, -> $x, $y { $x + $y } ... Inf;
And get the first eleven values (from 0 to 10) with:
say @short-fibs[^11];
or with:
say @fibs[^11];
Wait, you can get too the first 50 numbers from anonymous list itself:
say (^2,*+*...*)[^50]
That returns:
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
And some simple benchmark:
real 0m0.966s
user 0m0.842s
sys 0m0.080s
With:
$ time perl6 -e 'say (^2, *+* ... *)[^50]'
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