Fibonacci numbers with awk

awk 'BEGIN {a=1;b=1;for(i=0;i<'${NUM}';i++){print a;c=a+b;a=b;b=c}}'

Does not require input to function or complete. Number of iterations controlled by shell variable $NUM.

Sample Output

By: arcege

2009-09-06 03:05:55

awk awk

4 Alternatives + Submit Alt

Fibonacci numbers with awk

Another combination of seq and awk. Not very efficient, but sufficiently quick. Show Sample Output
This is sample output - yours may be different.
```
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
```
14

seq 50| awk 'BEGIN {a=1; b=1} {print a; c=a+b; a=b; b=c}'

kaan · 2009-03-24 20:39:24 37
Fibonacci numbers with awk

recursive version, "pure" AWK Show Sample Output
This is sample output - yours may be different.
```
0
1
1
2
3
5
8
13
21
34
55
89
144
233
377
610
987
1597
2584
4181
6765
10946
17711
28657
```
5

awk 'func f(n){return(n<2?n:f(n-1)+f(n-2))}BEGIN{while(a<24){print f(a++)}}'

unefunge · 2010-11-24 10:40:08 9
Fibonacci numbers with sh
This is sample output - yours may be different.
0

prev=0;next=1;echo $prev;while(true);do echo $next;sum=$(($prev+$next));prev=$next;next=$sum;sleep 1;done

sharfah · 2009-09-06 09:38:10 4
Fibonacci numbers with awk

only take the first field on each row to compute the fibo on this number Show Sample Output
This is sample output - yours may be different.
```
finish input with:
999
0
1
2
3
eof
26863810024485337815052569207027905710267776959038865271418527606059667101451514099303873236210167827650084004405807693119964697202348044908203804335127173454055409270617765081794282450393830849992803129229312
1
1
1
2
```
-5

gawk '{n=$1;a=0;b=1;c=1;for(i=1;i<n;i++){c=a+b;a=b;b=c};print c}' << eof

unixmonkey13930 · 2010-11-26 08:36:30 9

What Others Think

The Fibononacci sequence is supposed to start from 0, not 1.

sharfah · 787 weeks and 5 days ago

rahimhh21 · 109 weeks and 6 days ago

Perfecthomepugs · 101 weeks and 3 days ago

pugpuppies95 · 63 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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