“…Then the [n + l, n]-rule with help of four actions of arithmetic and well known formulas k=n k=1 k = (1/2)n(n + 1), k=n k=1 k 2 = (1/6)n(n + 1)(2n + 1), leads to the Klechkovski-Hakala formulas [11,15] Z n+l = K(n + l) + 1, n+l Z = K(n + l + 1), Z n,l = K(n + l + 1) − 2(l + 1) 2 + 1, n,l Z = K(n + l + 1) − 2l 2 , Z n = K(n + 1) − 1, n Z = K(2n) − 2(n − 1) 2 = (1/6) (2n − 1) 3 + 11(2n − 1) , Z l = K(2l + 1) + 1 = (1/6) (2l + 1) 3 + (5 − 2l) , Z nr = K(n r + 2) − 1.…”