A057745 Erroneous version of A083276.

1, 20, 400, 5362, 72078, 822518, 9417683

Offset: 0

Author

Keywords

• dead

Comments

This is considered erroneous because it counts as distinct two positions at ply 6 where in one case, an en passant capture is available but illegal, while in the other case, the en passant capture is not available. It is questionable whether two such positions should be considered equivalent, since the definition of position (as opposed to diagram) includes the information on whether en passant is available (i.e., pseudolegal), not whether it is legal. [Depending on the variant of chess that is played, it may be allowed to make otherwise "illegal" moves which expose one's king to a capture.] - M. F. Hasler, Mar 02 2022