752875208domain: NAppears in sequencesUnsigned member r=-8 of the family of Chebyshev sequences S_r(n) defined in A092184.at n=10A098308Numbers n >= 0 such that n^2 + n*(n+1)/2 is a square.at n=5A220186Positive octagonal numbers (A000567) that are squares (A000290) divided by 2.at n=2A259167