A323133 - OEIS

%I #10 Jan 19 2019 02:34:47

%S 1,6,7,29,46,170,299,969

%N Number of symmetric uncrossed unrooted knight's paths of length n on an infinite board.

%C A path is considered as symmetric if its "spine", i.e., the connection of the end points of the moves by straight lines, has mirror or point symmetry. The non-symmetric details of a single move are ignored.

%H Hugo Pfoertner, <a href="http://www.randomwalk.de/sequences/a323133.htm">Illustrations of symmetric uncrossed knight's paths of length <= 6</a>, (2019).

%e See Pfoertner link.

%Y Cf. A003192, A306176, A306178, A323131, A323132, A323134.

%K nonn,walk,more,hard

%O 1,2

%A _Hugo Pfoertner_, Jan 05 2019