And, to make it work as you were expecting, use Math::BigInt

use 5.016;
use Test::More qw(no_plan);
use Math::BigInt;

for (51..66) {
    # substr to remove 0b prefix
    my $s = substr(Math::BigInt->new("2")->bpow($_)->bdec->as_bin, 2);
    # Or: Math::BigInt->new("1")->blsft($_)->bdec->as_bin
    is length($s), $_, "1 << $_ -1";
}
__END__
ok 1 - 1 << 51 -1
ok 2 - 1 << 52 -1
ok 3 - 1 << 53 -1
ok 4 - 1 << 54 -1
ok 5 - 1 << 55 -1
ok 6 - 1 << 56 -1
ok 7 - 1 << 57 -1
ok 8 - 1 << 58 -1
ok 9 - 1 << 59 -1
ok 10 - 1 << 60 -1
ok 11 - 1 << 61 -1
ok 12 - 1 << 62 -1
ok 13 - 1 << 63 -1
ok 14 - 1 << 64 -1
ok 15 - 1 << 65 -1
ok 16 - 1 << 66 -1
1..16

[download]

Good Day,
    Dean

In reply to Re: Converting 2**54-1 to Binary by duelafn
in thread Converting 2**54-1 to Binary by philiprbrenan

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.