A164961
identification: the entry's rule defines the sequence for every index; tail: the sequence is the entry's tail after some prefix rows; match_*: finite agreement only.
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A085881 → basis A013609
(match reversed triangle, match triangle)
1 · 2, 2 · 12, 24, 12 · 120, 360, 360, 120 … row sums 1, 4, 48, 960, 26880, 967680, 42577920, …