A027150 a(n) = A027144(n, floor(n/2)).
1, 1, 4, 6, 12, 20, 80, 152, 304, 528, 2176, 4416, 8832, 15488, 64768, 135552, 271104, 477440, 2013184, 4289536, 8579072, 15144960, 64200704, 138407936, 276815872, 489431040, 2082406400, 4526702592, 9053405184, 16024403968
Offset: 0