my @primes = (3..60).grep: &is-prime;
print 'First four Giuga numbers: ';
put sort flat (2..4).map: -> $c {
@primes.combinations($c).map: {
my $n = [×] 2,|$_;
$n if all .map: { ($n / $_ - 1) %% $_ };
}
}
First 4 Giuga numbers: 30 858 1722 66198