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.

0, 1, 2, 6, 15, 40, 109, 302, 846, 2390, 6796, 19426, 55767, 160668, 464305, 1345282, 3906701, 11367696, 33135987, 96740610, 282831981, 827939880, 2426431239, 7118546874, 20904025380, 61439768166, 180725813478, 532004277518