The OEIS is supported by the many generous donors to the OEIS Foundation.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
%I #7 Feb 05 2019 21:15:07
%S 0,2,12,78,686,6056,59002,616522,7009264,86023126
%N Sum of distinct distances between n non-attacking rooks over all n X n chessboards.
%C a(n)/n! gives the expected number of distinct distances of n non-attacking rooks on a random n X n chessboard.
%C n!*A319476(n) <= a(n) <= n!*A320448(n).
%Y Cf. A319476, A320448.
%K nonn,more
%O 1,2
%A _Peter Kagey_, Feb 01 2019