1. select string_agg(rpad(t1.v || '*' || t2.v || '=' || t1.v * t2.v,6,' '), ' ')  as  " 9 * 9 multiplication "
    2.     from generate_series(1,9) t1(v),generate_series(1,9) t2(v)
    3. where t1.v>=t2.v group by t1.v order by t1.v;
    4. 1*1=1 
    5. 2*1=2  2*2=4 
    6. 3*1=3  3*2=6  3*3=9 
    7. 4*1=4  4*2=8  4*3=12 4*4=16
    8. 5*1=5  5*2=10 5*3=15 5*4=20 5*5=25
    9. 6*1=6  6*2=12 6*3=18 6*4=24 6*5=30 6*6=36
    10. 7*1=7  7*2=14 7*3=21 7*4=28 7*5=35 7*6=42 7*7=49
    11. 8*1=8  8*2=16 8*3=24 8*4=32 8*5=40 8*6=48 8*7=56 8*8=64
    12. 9*1=9  9*2=18 9*3=27 9*4=36 9*5=45 9*6=54 9*7=63 9*8=72 9*9=81