In minute 46 of the season finale, The Janus List, (episode 61, 3-24 aired 18 May 07) there was a shot of the United States flag flapping in the wind. In that shot there were 7 columns wide and 6 rows high for an even square of 42 stars, of a possible 48, with part of the left side cut out of the picture. This is possibly a shot of a flag that was used from 1912–1959 before Hawaii and Alaska joined the Union.
The current/actual US flag has 50 stars: 11 columns wide (left to right) and 9 rows high (top to bottom) with the odd rows (1-3-5-7-9) having 6 (5x6=30) stars and the even rows (2-4-6-8) having 5 stars (4x5=20). When looking at the flag every other line is 1 star short of being square used since 1953.