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%I #5 Mar 30 2012 17:30:18
%S 0,10,357,20156,1814395,239500794,43589145593,10461394943992,
%T 3201186852863991,1216451004088319990,562000363888803839989,
%U 310224200866619719679988,201645730563302817791999987
%N (n! - n)/2 for even n.
%D George E. Andrews, Number Theory, Dover Publ., NY 1971, p. 39.
%t Table[(n! - n)/2, {n, 2, 30, 2}]
%K nonn
%O 1,2
%A _Robert G. Wilson v_