

A144055


Number of n X n binary arrays, symmetric about main diagonal, with every 1 adjacent to at least one other 1, but at most one 1 adjacent horizontally and at most one 1 adjacent vertically.


0



1, 4, 13, 75, 765, 12167, 294579, 11514473, 740527130, 74320148705, 11850151989347, 3053892893918393, 1251352342040855094, 814829245618611538573, 849714505582240228227866
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