A122542
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.
-
A122542: Triangle T(n,k), 0 <= k <= n, read by rows, given by [0, 2, -1, 0, 0, 0, 0, 0, ...] DELTA [1, 0, 0, 0, 0, 0, 0, 0, ...] where DELTA is the operator defined in A084938.
(identification, match triangle)
1 · 0, 1 · 0, 2, 1 · 0, 2, 4, 1 … row sums 1, 1, 3, 7, 17, 41, 99, 239, …