122557domain: NPropertiesPrimalityPrimeyesAppears in sequencesNumber of n X n binary matrices, symmetric under 180 degree rotation, with no more than 3 ones in any 2 X 2 subblock.at n=6A141514Numerators of the partial sums of the reciprocals of the sum of unitary divisors function (A034448).at n=17A379513Prime numbersat n=11528