A275360 Maximum number of moves available to one side from a legal chess position with n pieces (with no additional pieces from promotion).

8, 35, 49, 63, 74, 85, 93, 99, 103, 109, 115

Offset

2,1

Comments

For completeness: If a side has two Bishops, those Bishops must be on opposite-colored squares (as in the original board configuration). Four promotion moves (to Knight, Bishop, Rook, or Queen) are available per Pawn per promotion square.

Sequence inspired by the Tim Krabbé link and a posting by Bernhard Sadlowski to rec.games.chess.computer on Oct 30 1996 (giving the H. H. Cross position -- see this a-file -- which supports the a(32) lower bound).

Terms a(13) through a(32) are respectively >= 119, 125, 129, 133, 137, 139, 140, 141, 143, 144, 144, 144, 144, 143, 142, 139, 128, 117, 105, 99.

Links

Table of n, a(n) for n=2..12.

T. Krabbé, Open Chess Diary, Item 195, Nov 29 2002: Mobility records

Rick L. Shepherd, Positions supporting initial terms and lower bounds.

Crossrefs

Sequence in context: A306126 A316308 A317263 * A281147 A217187 A214725

Adjacent sequences: A275357 A275358 A275359 * A275361 A275362 A275363

Keyword

nonn,fini,more

Author

Rick L. Shepherd, Jul 24 2016

Status

approved