28688

Appears in sequences

• Number of collinear point-triples in an n X n grid.at n=14A000938
• Number of permutations of length n which avoid the patterns 321, 1342, 3124.at n=20A116718
• Number of nX4 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 1 0 and 1 1 1 vertically.at n=9A208497
• Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 1 3 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 1 3 6 or 7.at n=9A252300
• Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-1) - b(n-2) - b(n-3), where a(0) = 1, a(1) = 3, a(2) = 5, b(0) = 2, b(1) = 4, b(2) = 6, and (a(n)) and (b(n)) are increasing complementary sequences.at n=23A295362