8346321domain: NAppears in sequencesa(n) and floor(a(n)/5) are both squares; i.e., squares which remain squares when written in base 5 and last digit is removed.at n=13A055812Expansion of (5-14*x+x^2)/((1-x)*(x^2-18*x+1)).at n=5A115032a(n) = sin( arcsin(n)- 2*arccos(n) )^2.at n=9A239608