A128813
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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A128813: Triangle of coefficients of (x+1)*(x+3)*(x+6)*...*(x+n(n+1)/2).
(identification, match triangle)
1 · 1, 1 · 1, 4, 3 · 1, 10, 27, 18 … row sums 1, 2, 8, 56, 616, 9856, 216832, …