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Calculate N!

Terminal - Calculate N!
echo $(( $(echo 1 "* "{2..10}) ))
2011-02-10 17:09:28
User: glaudiston
Functions: echo
2
Calculate N!

Alternatives

There are 8 alternatives - vote for the best!

Terminal - Alternatives
seq -s* 10 |bc
seq 10 | paste -sd* | bc
echo $(($(seq -s* 10)))
2011-02-10 18:44:53
User: minduim
Functions: echo seq
Tags: math factorial
1

Same as the seq/bc solution but without bc.

dc -e '10 [q]sq[dd1=q1-lxx*]dsxxp'
2011-02-16 19:00:21
User: mwgamera
Tags: math factorial
0

More readable version of factorial calculation using standard desktop calculator instead of bc.

Know a better way?

If you can do better, submit your command here.

What others think

calculates N! for values between 2 and 25.

echo $(( $(echo 1 "* "{2..26}) ))

-1569523520172457984

Kinda interesting. I'd be impressed if you could make a pascal's triangle in a one liner...

Comment by bartonski 224 weeks and 1 day ago

Interesting? I guess you are running a super computer.

Comment by RanyAlbeg 224 weeks and 1 day ago

Sorry. No supercomputers here. I did find the use of

"* "{2..10}

to create

* 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9 * 10

to be somewhat novel.

Comment by bartonski 224 weeks and 1 day ago

the pascal's triangle is a hard task... but i'm trying...

I'm so close...

lines=6; eval echo -e "{1..$lines}\\\n" | while read i; do eval "array$i=( $(echo {1..$i} ) ); echo \${array$((i-1))[@]}"; done;

with this I can recover the array from previous line... with some more work I can do it.

Comment by glaudiston 224 weeks and 1 day ago

@glaudiston I've solved it with a couple of nested for loops, but I'm still waiting for my command to be moderated.

Comment by flatcap 224 weeks and 1 day ago

@bartonski, done, a one line pascal's triangle;

l=10;for((i=0;i<$l;i++));do eval "a$i=($(pv=1;v=1;for((j=0;j<$l;j++));do [ $i -eq 0 -o $j -eq 0 ]&&{ v=1 && pv=1; }||v=$((pv+a$((i-1))[$((j))]));echo -n "$v ";pv=$v;done;));";eval "echo \"\${a$i[@]}\"";done | column -t;
Comment by glaudiston 224 weeks ago

Your point of view

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