perl -wle 'use Data::Dumper; my @buckets; my $buckets = 4; @a = 1 .. 14; push @buckets, [ grep defined, @a[ map { $_ * $buckets } 0 .. @a / $buckets ] ] xor shift @a for 1 .. 1 + @a / $buckets; print Dumper( @buckets )'

##</code><code>##

Useless use of logical xor in void context at -e line 1.
$VAR1 = [
          1,
          5,
          9,
          13
        ];
$VAR2 = [
          2,
          6,
          10,
          14
        ];
$VAR3 = [
          3,
          7,
          11
        ];
$VAR4 = [
          4,
          8,
          12
        ];