58731

Appears in sequences

• Number T(n,k) of equivalence classes of ways of placing k 3 X 3 tiles in an n X 10 rectangle under all symmetry operations of the rectangle; irregular triangle T(n,k), n>=3, 0<=k<=3*floor(n/3), read by rows.at n=49A238592
• a(n) is the number of permutations of length n that avoid the pattern 231 and the mesh pattern (12, 409) or the same sequence for the mesh pattern (12, 473).at n=11A289451