57442domain: NAppears in sequencesNumber of (n+1)X(n+1) -8..8 symmetric matrices with every 2X2 subblock having sum zero and two or three distinct values.at n=8A211469Expansion of Product_{k>=1} 1/((1-x^(3*k-1))*(1-x^(3*k-2)))^k.at n=34A262883Total number of parity changes within the blocks of all partitions of [n].at n=9A363496