zak seidov <zakseidov at yahoo.com> wrote: :--- Antti Karttunen <antti.karttunen at gmail.com> wrote: [...] :> "Integers n, such that A117532(1..n) contains all :> integers from 1 to n." :> if it's not too short. : :Yes, the seq' VERY short: :A2=(1,2) :(from first 2,000 terms of A117532) Well yes, 2 * sum(1..n) is divisible by n. :) Hugo V.