A147728 Number of permutations of 1..n with all sums of 2 through 6 adjacent terms respectively unique.
1, 2, 6, 16, 54, 232, 936, 3880, 17302, 81584, 409012, 2138674, 11754832, 66857094, 399774882, 2469567300, 15804526682
Offset: 1
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