21497

Appears in sequences

• Number of matchings in graph C_{4} X P_{n}.at n=4A033516
• Number of matchings in graph P_{2} X P_{4} X P_{n}.at n=2A033527
• Row sums of triangle A084408.at n=35A084411
• Array read by antidiagonals: T(m,n) is the number of matchings in the stacked prism graph C_m X P_n.at n=24A287428
• Number of integer compositions of n where adjacent parts are indivisible (either way) and the last and first part are also indivisible (either way).at n=31A318727
• Row sums of A325433.at n=42A325434
• a(n) is the number of 5 element sets of distinct integer sided rectangles that fill an n X n square.at n=15A387241