A084949
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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A257608: 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) = 9*x + 1.
(match row sums)
1 · 1, 1 · 1, 20, 1 · 1, 219, 219, 1 … row sums 1, 2, 22, 440, 12760, 484880, 22789360, …