#!/usr/bin/env perl
use warnings;
use strict;
use feature qw{ say };

use List::PowerSet qw{ powerset };

my %groups;

while (<DATA>) {
    my @numbers = split;
    for my $ps (@{ powerset(@numbers) }) {
        next if @$ps < 2;
        $groups{"@$ps"}++;
    }
}

for my $group (keys %groups) {
    next if $groups{$group} == 1;
    say "$group repeated $groups{$group} times";
}

__DATA__
1 2 5 9
1 2 5 10
4 5 10 12
5 9 10 11