Number of ways a black pawn (from any starting square on the second back rank) can (theoretically) end on the n-th square of the leftmost file counted from the back rank.

A062106

Number of ways a black pawn (from any starting square on the second back rank) can (theoretically) end on the n-th square of the leftmost file counted from the back rank.

Terms

    a(0) =0a(1) =1a(2) =2a(3) =6a(4) =15a(5) =40a(6) =109a(7) =302a(8) =846a(9) =2390a(10) =6796a(11) =19426a(12) =55767a(13) =160668a(14) =464305a(15) =1345282a(16) =3906701a(17) =11367696a(18) =33135987a(19) =96740610a(20) =282831981a(21) =827939880a(22) =2426431239a(23) =7118546874a(24) =20904025380a(25) =61439768166a(26) =180725813478a(27) =532004277518

External references