my @array = [];

BTW, I don't know what you expected the quoted statement from the OPed code to do, but what it does is to initialize  @array with a single element: a reference to an empty anonymous array.

c:\@Work\Perl\monks>perl -wMstrict -le
"use Data::Dump qw(dd);
 ;;
 my @array = [];
 dd \@array;
 ;;
 $array[2][3] = 1;
 $array[3][4] = 2;
 $array[2][6] = 10;
 ;;
 dd \@array;
"
[[]]

[
  [],
  undef,
  [undef, undef, undef, 1, undef, undef, 10],
  [undef, undef, undef, undef, 2],
]
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