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Fibonacci numbers with awk

Terminal - 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}}'
2009-09-06 03:05:55
User: arcege
Functions: awk
0
Fibonacci numbers with awk

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

Alternatives

There is 1 alternative - vote for the best!

Terminal - Alternatives
seq 50| awk 'BEGIN {a=1; b=1} {print a; c=a+b; a=b; b=c}'
2009-03-24 20:39:24
User: kaan
Functions: awk seq
Tags: awk seq
13

Another combination of seq and awk. Not very efficient, but sufficiently quick.

awk 'func f(n){return(n<2?n:f(n-1)+f(n-2))}BEGIN{while(a<24){print f(a++)}}'
2010-11-24 10:40:08
User: unefunge
Functions: awk
Tags: awk
5

recursive version, "pure" AWK

prev=0;next=1;echo $prev;while(true);do echo $next;sum=$(($prev+$next));prev=$next;next=$sum;sleep 1;done
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
2010-11-26 08:36:30
Functions: gawk
Tags: awk
-5

only take the first field on each row to compute the fibo on this number

Know a better way?

If you can do better, submit your command here.

What others think

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

Comment by sharfah 298 weeks and 4 days ago

Your point of view

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