On Thu, Jul 16, 2015 at 2:16 PM, юрий герасимов <2stepan at rambler.ru> wrote: > A pair of number x and y called xenial if the sum of A069289(x) and > A069289(y) is equal to the sum of A008472(x) and A008472(y) where > A069859(n) is n*sum( p | n, 1/p ) this is A069359, neither A069289, nor A069859. M.