Number of positions in game "Connect Four" (played on usual 6-row, 7-column board) after n moves, up to reflection.

A013582

Number of positions in game "Connect Four" (played on usual 6-row, 7-column board) after n moves, up to reflection.

Terms

    a(0) =1a(1) =4a(2) =25a(3) =121a(4) =568a(5) =2144a(6) =8231a(7) =27473a(8) =92244a(9) =279241a(10) =831581a(11) =2284733a(12) =6118941a(13) =15465573a(14) =37720667a(15) =88273017a(16) =197300906a(17) =429114775a(18) =881951878a(19) =1784140720a(20) =3373100313a(21) =6336692489a(22) =11005448210a(23) =19131647821a(24) =30415473928a(25) =48633111249

External references