Number of (2n+1) X (2n+1) black-and-white grids that are legal for crossword puzzles.

A323838

Number of (2n+1) X (2n+1) black-and-white grids that are legal for crossword puzzles.

Terms

    a(0) =1a(1) =15a(2) =397a(3) =35324a(4) =18446134a(5) =41752489852

External references