meditate on the output of this: :) 
use strict;

for (0..20,) {
   $a = dec2bin($_+1);
   $b = dec2bin($_);
   print "$a = ", $_ + 1, "\n",
         "$b = ", $_, "\n",
         "--------\n", 
         dec2bin(($_+1) & $_), " = ", 
         (($_+1) & $_), "\n\n";

}

# Perl Cookbook recipe 2.4.
sub dec2bin {
   my $s = unpack("B32", pack("N",shift));
   #$s =~ s/^0+(?=\d)//;
   $s = substr($s,-8,8);
   return $s;
}

[download]
UPDATE: thanks tachyon!

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)
-->

In reply to (jeffa) Re: Bitwise & with large numbers by jeffa
in thread Bitwise & with large numbers by Anonymous Monk

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