Number of possible 3 X n arrangements of black and white squares that can form three consecutive rows in an n X n crossword puzzle.

A133253

Number of possible 3 X n arrangements of black and white squares that can form three consecutive rows in an n X n crossword puzzle.

Terms

    a(0) =1a(1) =23a(2) =159a(3) =649a(4) =2424a(5) =9574a(6) =39913a(7) =166639a(8) =678898

External references