Consider digits 1 though 9 arranged in a cylindrical pattern
1 2 3
4 5 6
7 8 9
1 2 3
4 5 6
7 8 9
The repeating decimal expansion 142857 of 1/7 traces out a parallelogram on the grid, only always traveling to adjacent digits.
The digits that are a multiple of three, 0369, are not used.
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