209820

Appears in sequences

• Coordination sequence for 6-dimensional cubic lattice.at n=13A008414
• Triangle read by rows: T(n,k) is number of paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(2,1), U=(1,2), or d=(1,-1) and having abscissa of first return equal to 3k.at n=29A108439
• Expansion of psi(-q^3) / psi(-q)^3 in powers of q where psi() is a Ramanujan theta function.at n=26A132974
• Expansion of psi(q^3) / psi(q)^3 in powers of q where psi() is a Ramanujan theta function.at n=26A132979
• Triangle read by rows: T(n,k) is the number of L-convex polyominoes of semiperimeter n, having k maximal rectangles (n >= 2, 1 <= k <= floor(n/2)). An L-convex polyomino is a convex polyomino in which any two cells can be connected by a path internal to the polyomino and which has at most 1 change of direction (i.e., one of the four orientations of the letter L). A maximal rectangle in an L-convex polyomino P is a rectangle included in P that is maximal with respect to inclusion.at n=39A181368
• Expansion of phi(-q^3) / phi(-q)^3 in powers of q where phi() is a Ramanujan theta function.at n=13A259662