#!/usr/bin/perl -w

#

# Caluclate Buenos Aires constant - https://youtu.be/_gCKX6VMvmU

# Sum of infinite series method

# (C)Nov 26 2020 Pegasus Epsilon - Educational Purposes Only

use strict;

use bignum ( p => -4000 );

use v5.10;

@_ = map { chomp; $_ } <DATA>; # read saved data

close DATA;

my ($n,$v,$b) = ($_[$#_] =~ /(.*),(.*),(.*)/); # split the last entry

@_ = map { s/,(.*)//; $_ } @_; # discard the constant convergence log

open my $data, '>>', $0;

say "Resuming from $n (Buenos Aires constant = $b)...";

$v *= $n;

for (;;) {

$n += 2;

my $sqrt = sqrt($n);

unless ($sqrt == int($sqrt)) {

foreach my $d (@_) {

last if 0 == $n % $d;

next if $d < $sqrt;

$b += ($n - 1) / $v;

say "$n is prime, Buenos Aires constant = $b...";

say $data "$n,$v,$b";

push @_, $n;

$v *= $n;

last;

}

}

}

__DATA__

2,1,1

3,2,2