DSolve[D[y[x], x] == (y[x] + 1)*x, y[x], x]
DSolve[{D[y[x], x] == (y[x] + 1)*x, y[0] == 1}, y[x], x]

max = 10;
h = 0.1;
x0 = 0.0;
y0 = 0.1;
f [x_, y_] := (y + 1)* x;
iksy = Table[ x0 + (i - 1)*h, {i, max}]
rob = y0;
Do[{rob = rob + h *f[iksy[[i]], rob], igreki[i] = rob}, {i, max}]
ygreki = Table[igreki[i], {i, 1, max}]
(* lub
...
rob=y0;
ygreki={};
Do[{rob=rob+h*f[iksy[[i]],rob],ygreki=Append[ygreki,rob]},{i,max}]
*)

alaMaKota = Table [{iksy [[i]], ygreki[[i]]}, {i, 1, max}]