# this works for all n

sub MAIN( Int $n = 11 )
{
    my $ln = ( $n * $n ).chars + 1;
    my $li = $n.chars + 1;

    header;
    line $_ for ( 1 .. $n );

    sub line( $i )
    {
        my @n = ( ( $i .. $n ) X* $i ).map({ sprintf( "%{$ln}s", $_ ) });
        my @e = ( ' ' xx ( $ln * ( $i - 1 ) ) );
        say sprintf( "%{$li}s", $i ), '|', @e.join,  @n.join;
    }

    sub header
    {
        my @h = ( 1 .. $n ).map({ sprintf( "%{$ln}s", $_ ) });
        say sprintf( "%{$li}s", "x" ), '|', @h.join;
        say ( '-' xx $li ).join, "+", ( '-' xx ( $n * $ln ) ).join;
    }
}