# 1
$n=length$a++*$a/2;map{map{printf" %$n.d",++$k}2..$_;print$/}2..$a

# 2
print+(map$"x(length(($a+1)*$a/2)+1-length++$l).$l,2..$_),$/for 2..$a+1

# 3
print+(map$"x(($a>13?4:$a>3?3:2)-length++$l).$l,2..$_),$/for 2..$a+1