Number of possible 2 X n arrangements of black and white squares that can form two consecutive rows in an n X n crossword puzzle.

A133226

Number of possible 2 X n arrangements of black and white squares that can form two consecutive rows in an n X n crossword puzzle.

Terms

    a(0) =1a(1) =9a(2) =36a(3) =98a(4) =246a(5) =646a(6) =1777a(7) =4883a(8) =13120a(9) =34642a(10) =90976a(11) =239160a(12) =629427

External references