A027148 a(n) = A027144(2n-1, n-1).

1, 6, 20, 152, 528, 4416, 15488, 135552, 477440, 4289536, 15144960, 138407936, 489431040, 4526702592, 16024403968, 149528084480, 529747476480, 4977103994880, 17643662213120, 166668216041472, 591119702294528, 5608619676532736

Offset: 1

Author

Clark Kimberling

Keywords

• nonn