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Pascal's triangle

Terminal - 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;

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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

Comment by glaudiston 232 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;));";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

Comment by glaudiston 232 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

Comment by glaudiston 232 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
Comment by glaudiston 232 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
Comment by glaudiston 232 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.

Comment by glaudiston 232 weeks and 4 days ago

Very pretty :-)

Comment by flatcap 232 weeks and 3 days ago

Your point of view

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