✓ Mathematica : cpu = 0.19254 (sec), leaf count = 99
DSolve[Derivative[1][y][x] == 1 - x/4 + x^2/16 - (5*x^3)/64 + (5*x^4)/128 - (3*x^5)/256 + x^6/512 - (x*y[x])/2 + (7*x^2*y[x])/16 - (3*x^3*y[x])/16 + (3*x^4*y[x])/64 + y[x]^2 - (3*x*y[x]^2)/4 + (3*x^2*y[x]^2)/8 + y[x]^3,y[x],x]
✓ Maple : cpu = 0.098 (sec), leaf count = 39
dsolve(diff(y(x),x) = -1/4*x+1+y(x)^2+7/16*x^2*y(x)-1/2*x*y(x)+5/128*x^4-5/64*x^3+1/16*x^2+y(x)^3+3/8*y(x)^2*x^2-3/4*x*y(x)^2+3/64*y(x)*x^4-3/16*x^3*y(x)+1/512*x^6-3/256*x^5,y(x))