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 A289222 Triangle read by rows: T(n, k) is the number of ways to select k disjoint point triples from an n X n X n triangular point grid, each point triple forming a 2 X 2 X 2 triangle. 9
 1, 1, 1, 1, 4, 0, 1, 9, 12, 4, 1, 16, 66, 82, 13, 0, 1, 25, 204, 670, 859, 420, 76, 0, 1, 36, 480, 3028, 9585, 15108, 10956, 2910, 231, 2, 1, 49, 960, 9780, 56520, 190371, 371016, 404746, 235380, 68793, 9030, 252, 0, 1, 64, 1722, 25574, 231635, 1336320, 4988324 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS The row index starts from 1. The column index k runs from 0 to floor(n*(n+1)/6), which is a trivial upper bound for the maximal number of 2 X 2 X 2 triangles that can be selected from an n X n X n triangular grid. Rotations and reflections of a selection are regarded as different. If they are not to be counted, see A289229. LINKS EXAMPLE The triangle begins:   1;   1,  1;   1,  4,   0;   1,  9,  12,    4;   1, 16,  66,   82,   13,     0;   1, 25, 204,  670,  859,   420,    76,    0;   1, 36, 480, 3028, 9585, 15108, 10956, 2910, 231, 2; CROSSREFS Cf. A289229, A289233. Columns 2 to 8: A000290, A289223, A289224, A289225, A289226, A289227, A289228. Sequence in context: A199786 A189245 A342372 * A121301 A059056 A344393 Adjacent sequences:  A289219 A289220 A289221 * A289223 A289224 A289225 KEYWORD tabf,nonn AUTHOR Heinrich Ludwig, Jul 03 2017 STATUS approved

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Last modified September 17 15:51 EDT 2021. Contains 347478 sequences. (Running on oeis4.)