A154233
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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A154233: Triangle T(n, k) = T(n-1, k) + T(n-1, k-1) + (n^2 +n -1)*T(n-2, k-1), read by rows.
(identification, match reversed triangle, match triangle)
1 · 1, 1 · 1, 7, 1 · 1, 19, 19, 1 … row sums 1, 2, 9, 40, 251, 1662, 13615, 118640, …