function* gammaGenerator(n) {
const step = 0.01;
const offset = -offsetN * (1 / step),
arrayL = offset + (1 / step) * n;
const z = [],
f = [];
for (let i = 0; i <= arrayL; ++i) {
z[i] = {
x: i * step - offset * step,
y: Lanczos(i * step - offset * step)
};
yield z;
}
}