Seidel method and iterations. How is K? And how is the method of iteration and Seidel?

Question

Mathematics

Good day! Can you please tell me how k=23 and k=21 are calculated in the example
And where is (0.9999783; 2.00000017; 2.9998545) taken for the iteration method?

Answer 1

23 (or 21) times you need to apply the discrete analogue of the differential operator to the initial vector (multiply by the matrix and add beta, in other words) to get the answer.

Answer 2

It is written in Russian in white: "We will continue the iterative process until the condition is fulfilled ...".
That's how the condition was fulfilled, so we stopped the loop and got k.