Print Powers of 2 to 2^64

powers_of_2_in_decimal.pl

#!/usr/bin/env perl
use bignum;
$a=1;
for(0..64){
  printf "%2s%21s\n", $_, $a;
  $a<<=1;
}

# (perl)$ perl -Mbignum -E '$a=1;for(0..64){say" "x($_<10).$_." "x(21-length($a)).$a;$a<<=1}'
# (perl)$ perl -Mbignum -E '$a=1;for(0..64){printf"%2s%21s\n",$_,$a;$a<<=1}'
# (bash)$ p=0 v=1;until [ $p -gt 64 ];do printf '%2s%21s\n' $((p++)) $v;((v<<=1));done