3994080domain: NAppears in sequencesNumber of ways of writing n as a sum of 16 squares.at n=8A000152a(n) = (7*n+3)*(7*n+5)*(7*n+6).at n=22A001561Theta series of D_16 lattice.at n=4A022047Expansion of theta_4(q)^16 in powers of q = exp(Pi i t).at n=8A319307