Question: Error in Sequence command

 Dear fellows
I have the problme with first seq command.
for i while i <= M1-2 do for j while j <= M1-2 do for k while k <= M1 do Eq[i, jk] := simplify(eval(R, [x = i/(M1-2.), y = j/(M1-2.), t = k/(M1-1.)])) = 0 end do end do end do:

Sol := fsolve({seq(BC1[m8, m9]$m8 = 1 .. M1, m9 = 1 .. M1), seq(BC2[m10, m11]$m10 = 1 .. M1, m11 = 1 .. M1), seq(BC3[m12, m13]$m12 = 1 .. M1, m13 = 1 .. M1), seq(BC4[m14, m15]$m14 = 1 .. M1, m15 = 1 .. M1), seq(IC1[m4, m5]$m4 = 0 .. M1, m5 = 1 .. M1), seq(IC2[m6, m7]$m6 = 0 .. M1, m7 = 1 .. M1), seq(Eq[m1, m2, m3]$m1 = 1 .. M1-2, m2 = 1 .. M1-2, m3 = 1 .. M1-1)});

Got the following error.

Error, invalid input: seq expects its 3rd argument, step, to be of type numeric, but received m3 = 1 .. 1

Please help me in this regard.