52505domain: NAppears in sequencesHalf the number of n X n nonnegative integer arrays with every 2 X 2 subblock summing to 2.at n=12A145012Arises from a construction of equiangular lines in complex space of dimension 2.at n=21A239909Number of partitions of n such that m(greatest part) >= m(1), where m = multiplicity.at n=49A240080