sub perms {
    my ($n, $min) = @_;
    $min //= 2;
    return [] if $n <= 0;  
    return [$n] if $n <= $min;

    my @r;
    foreach my $i ($min .. $n) {
        my $left = $n - $i;
        next if $left < $min;
        my @p = perms $left, $i;
        foreach my $p (@p) {
            push @r, [@$p, $i];  
        }
    }
    @r;
}

say "[@$_"] for perms 7;
__END__
[2 3 2]
[3 4]
[2 5]