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;
Sample Output
1  1   1   1    1    1     1     1      1      1
1  2   3   4    5    6     7     8      9      10
1  3   6   10   15   21    28    36     45     55
1  4   10  20   35   56    84    120    165    220
1  5   15  35   70   126   210   330    495    715
1  6   21  56   126  252   462   792    1287   2002
1  7   28  84   210  462   924   1716   3003   5005
1  8   36  120  330  792   1716  3432   6435   11440
1  9   45  165  495  1287  3003  6435   12870  24310
1  10  55  220  715  2002  5005  11440  24310  48620

0
2011-02-11 17:00:20

What Others Think

If you want only the triangle: l=10;for((i=0;i<$l;i++));do eval "a$i=($(pv=1;v=1;for((j=0;j<$l-$i;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$i[@]}\"";done | column -t; 1 1 1 1 1 1 1 1 1 1 1 2 3 4 5 6 7 8 9 1 3 6 10 15 21 28 36 1 4 10 20 35 56 84 1 5 15 35 70 126 1 6 21 56 126 1 7 28 84 1 8 36 1 9 1
glaudiston · 400 weeks and 5 days ago
l=15;for((i=0;i<$l;i++));do eval "a$i=($(pv=1;v=1;for((j=0;j<$l-$i;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 "$(for((k=0;k<=$i;k+ +)); do eval "echo -n \"\$((a\$((i-k))[k])) \""; done)";done; 1 1 1 1 2 1 1 3 3 1 1 4 6 4 1 1 5 10 10 5 1 1 6 15 20 15 6 1 1 7 21 35 35 21 7 1 1 8 28 56 70 56 28 8 1 1 9 36 84 126 126 84 36 9 1 1 10 45 120 210 252 210 120 45 10 1 1 11 55 165 330 462 462 330 165 55 11 1 1 12 66 220 495 792 924 792 495 220 66 12 1 1 13 78 286 715 1287 1716 1716 1287 715 286 78 13 1 1 14 91 364 1001 2002 3003 3432 3003 2002 1001 364 91 14 1
glaudiston · 400 weeks and 4 days ago
{ l=15;for((i=0;i<$l;i++));do eval "a$i=($(pv=1;v=1;for((j=0;j<$l-$i;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;));";o="$(eval echo "$(for((k=0;k 1 1 1 1 2 1 1 3 3 1 1 4 6 4 1 1 5 10 10 5 1 1 6 15 20 15 6 1 1 7 21 35 35 21 7 1 1 8 28 56 70 56 28 8 1 1 9 36 84 126 126 84 36 9 1 1 10 45 120 210 252 210 120 45 10 1 1 11 55 165 330 462 462 330 165 55 11 1 1 12 66 220 495 792 924 792 495 220 66 12 1 1 13 78 286 715 1287 1716 1716 1287 715 286 78 13 1 1 14 91 364 1001 2002 3003 3432 3003 2002 1001 364 91 14 1
glaudiston · 400 weeks and 4 days ago
The last coment show the triangle nicely. { l=15;for((i=0;i<$l;i++));do eval "a$i=($(pv=1;v=1;for((j=0;j<$l-$i;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;));";o="$(eval echo "$(for((k=0;k<=$i;k++)); do eval "echo -n \"\$((a\$((i-k))[k])) \""; done)")";echo "$o";s="${#o}"; done; } | while read l; do j=$((s-${#l}/2)); echo "$(while ((i++ < j)); do echo -n " ";done;)$l";done 1 1 1 1 2 1 1 3 3 1 1 4 6 4 1 1 5 10 10 5 1 1 6 15 20 15 6 1 1 7 21 35 35 21 7 1 1 8 28 56 70 56 28 8 1 1 9 36 84 126 126 84 36 9 1 1 10 45 120 210 252 210 120 45 10 1 1 11 55 165 330 462 462 330 165 55 11 1 1 12 66 220 495 792 924 792 495 220 66 12 1 1 13 78 286 715 1287 1716 1716 1287 715 286 78 13 1 1 14 91 364 1001 2002 3003 3432 3003 2002 1001 364 91 14 1
glaudiston · 400 weeks and 4 days ago
arrrg... the space on begin of line as been cuted-out for persistence I WILL try again, with $. in the start of line: { l=15;for((i=0;i<$l;i++));do eval "a$i=($(pv=1;v=1;for((j=0;j<$l-$i;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;));";o="$(eval echo "$(for((k=0;k<=$i;k++)); do eval "echo -n \"\$((a\$((i-k))[k])) \""; done)")";echo "$o";s="${#o}"; done; } | while read l; do j=$((s-${#l}/2)); echo "$(while ((i++ < j)); do echo -n " ";done;)$l";done . 1 . 1 1 . 1 2 1 . 1 3 3 1 . 1 4 6 4 1 . 1 5 10 10 5 1 . 1 6 15 20 15 6 1 . 1 7 21 35 35 21 7 1 . 1 8 28 56 70 56 28 8 1 . 1 9 36 84 126 126 84 36 9 1 . 1 10 45 120 210 252 210 120 45 10 1 . 1 11 55 165 330 462 462 330 165 55 11 1 . 1 12 66 220 495 792 924 792 495 220 66 12 1 . 1 13 78 286 715 1287 1716 1716 1287 715 286 78 13 1 . 1 14 91 364 1001 2002 3003 3432 3003 2002 1001 364 91 14 1
glaudiston · 400 weeks and 4 days ago
aff... forget it... but if you test the command in shell will get a formated output like a perfect triangle.
glaudiston · 400 weeks and 4 days ago
Very pretty :-)
flatcap · 400 weeks and 4 days ago

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