A257610
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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A257610: Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 3*x + 2.
(identification, match reversed triangle, match triangle)
1 · 2, 2 · 4, 20, 4 · 8, 132, 132, 8 … row sums 1, 4, 28, 280, 3640, 58240, 1106560, …