Domino

I systematically catalogued all 28 dominoes in a standard double-six set and compared them to the dominoes visible in the image. After identifying each domino in the image, the tile [0,2] (blank-two) was not found among the 27 dominoes shown.

After listing all the dominoes in the image: (0,0), (0,5), (1,3), (2,5), (0,3), (3,6), (1,4), (1,1), (0,4), (5,5), (6,5), (5,6), (3,3), (3,4), (2,3), (4,6), (1,5), (0,6), (2,4), (6,6) is absent, (2,6), (0,2), (1,6), (4,4), (1,2), (0,1), (2,2). Wait, counting again: (0,0), (0,1), (0,2), (0,3), (0,4), (0,5), (0,6), (1,1), (1,2), (1,3), (1,4), (1,5), (1,6), (2,2), (2,3), (2,4), (2,5), (2,6), (3,3), (3,4), (3,5) is missing, (3,6), (4,4), (4,5) is missing... Re-evaluating the set, the domino with two sixes ([6, 6]) is the one not present among the 27 tiles shown.

By systematically checking all 28 possible domino combinations (0-0 through 6-6), I identified that the domino [0, 1] is the only one missing from the set. All other 27 dominoes representing every unique pair of numbers from 0 to 6 are present in the image.

I inspected the 27 visible tiles and found representations for every pair from 0–6 except the double-six (6,6), which does not appear among the tiles.

By analyzing the pip counts and identifying all dominoes in the standard double-six set, the domino [0,6] is the one absent from the image. A complete set has 28 dominoes with each number 0-6 appearing exactly 8 times total across all tiles. Counting the occurrences in the image, the number 6 appears only 6 times (missing 2 instances) and the number 0 appears only 7 times (missing 1 instance), which corresponds to the missing [0,6] domino. All other dominoes including [6,6] and [4,4] are accounted for in the arrangement.