For the Paschen series the values of n1 and n2 in the expression △E=RH×c[1n21−1n22]
Paschen series of lines are obtained when an electron de-excites from higher orbits to 3rd orbit
For positive integers n1,n2 the value of the expression (1+i)n1+(1+i3)n1+(1+i5)n2 + (1+i7)n2 where i=2√−1 is a real number if and only if