A142458
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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A142458: Triangle T(n,k) read by rows: T(n,k) = 1 if k=1 or k=n, otherwise T(n,k) = (3*n-3*k+1)*T(n-1,k-1) + (3*k-2)*T(n-1,k).
(identification, match reversed triangle, match triangle)
1 · 1, 1 · 1, 8, 1 · 1, 39, 39, 1 … row sums 1, 2, 10, 80, 880, 12320, 209440, …