``````#!/usr/bin/env perl
use strict;
use warnings;

# Find the first N abundant, deficient, or perfect numbers.

use Math::Prime::Util qw/divisor_sum next_prime is_prime/;

my \$count = shift || 20;
my \$type = lc(shift || 'abundant');

my \$p = 0;
if (\$type eq 'abundant') {
while (\$count-- > 0) {
do { \$p++ } while divisor_sum(\$p)-\$p <= \$p;
print "\$p\n";
}
} elsif (\$type eq 'deficient') {
while (\$count-- > 0) {
do { \$p++ } while divisor_sum(\$p)-\$p >= \$p;
print "\$p\n";
}
} elsif (\$type eq 'perfect') {
# We'll use the chain of work by Euclid, Ibn al-Haytham, Euler, and others.
# We just look for 2^(p-1)*(2^p-1) where 2^p-1 is prime.
# Basically we're just finding Mersenne primes.
# It's possible there are odd perfect numbers larger than 10^1500.
do { require Math::BigInt;  Math::BigInt->import(try=>"GMP,Pari"); };
while (\$count-- > 0) {
while (1) {
\$p = next_prime(\$p);
last if is_prime(Math::BigInt->new(2)->bpow(\$p)->bdec);
}
print Math::BigInt->from_bin( '0b' . '1'x\$p . '0'x(\$p-1) ), "\n";
}
} else {
die "Unknown type: \$type\n";
}
``````