Rで9×9掛け算表を表示する（ネタ） ref: http://qiita.com/kurogelee/items/73852c61e423dc1ae6eb

file0.txt

> 1:9 %*% t(1:9)
      [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9]
 [1,]    1    2    3    4    5    6    7    8    9
 [2,]    2    4    6    8   10   12   14   16   18
 [3,]    3    6    9   12   15   18   21   24   27
 [4,]    4    8   12   16   20   24   28   32   36
 [5,]    5   10   15   20   25   30   35   40   45
 [6,]    6   12   18   24   30   36   42   48   54
 [7,]    7   14   21   28   35   42   49   56   63
 [8,]    8   16   24   32   40   48   56   64   72
 [9,]    9   18   27   36   45   54   63   72   81