Examples in which the MMA 11.0 gives incorrect or strange solutions.
Example1:
Sum[Floor[5/5^k], {k, 1, \[Infinity]}](* It should be 1 *)
Example2:
eq = y[n] - 1 - 1*Sqrt[y[n]] - y[n + 1];
sol = First@RSolve[{eq == 0, y[0] == 1}, y[n], n];
Table[(y[n] /. sol), {n, 10}] // N
RecurrenceTable[{eq == 0, y[0] == 1}, y,
{n, 10}] // N(*Answers not the same *)
Example3:
eqn5 = (y'[x])^2 + y'[x]*y[x] - x == 0;
DSolve[{eqn5}, y[x], x](* strange results *)
Example4:
FourierTransform[Exp[a*t ]/t, t, \[Omega]](*incorrect answer *)
Example5:
InverseLaplaceTransform[Coth[s], s, t]
InverseLaplaceTransform[Tanh[s], s, t]
InverseLaplaceTransform[Sech[s], s, t]
InverseLaplaceTransform[Csch[s], s, t]
(* strange results *)
Example6:
Integrate[Sqrt[Exp[I*t]^2 - 1], {t, 0, Pi}](*incorrect answer *)
Example7:
<< Quaternions`
Exp[Quaternion[1, 0, 0, 0]]
(*bug or errors*)
Example8:
Integrate[Sin[q]^2/Sinh[q]^2, {q, 0, \[Infinity]}](*incorrect answer *)