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%I #3 Mar 30 2012 17:37:01
%S 2,2,12,174,2880,67560,1905960,63251370,2418101280,104707709820,
%T 5063563002960,270496771471080,15820958657223720,1005528154974983640,
%U 69006386355388962480,5085661679602382028150
%N Doubles (index 2+) under "BGJ" (reversible, element, labeled) transform.
%K nonn
%O 1,1
%A _Christian G. Bower_