cp's OEIS Frontend

A348044 The nearest common ancestor of n and n^2 in the Doudna tree (A005940).

%I A348044 #9 Jan 30 2022 09:51:32
%S A348044 1,2,2,4,2,2,2,8,4,2,2,2,2,2,2,16,2,4,2,2,2,2,2,2,4,2,8,2,2,2,2,32,2,
%T A348044 2,2,4,2,2,2,2,2,2,2,2,2,2,2,2,4,4,2,2,2,8,2,2,2,2,2,2,2,2,2,64,2,2,2,
%U A348044 2,2,2,2,4,2,2,4,2,2,2,2,2,16,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,4,2,4,2,2,2,2,2
%N A348044 The nearest common ancestor of n and n^2 in the Doudna tree (A005940).
%H A348044 Antti Karttunen, <a href="/A348044/b348044.txt">Table of n, a(n) for n = 1..20000</a>
%H A348044 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a>
%F A348044 a(n) = A348041(n, n^2) = A348042(n, n) = A348043(n, n).
%o A348044 (PARI) A348044(n) = A348041sq(n,n*n); \\ Uses also code from A348041.
%Y A348044 Main diagonal of A348042 and A348043.
%Y A348044 Cf. A102750 (the positions of 2's).
%Y A348044 Cf. A005940, A156552, A348041.
%K A348044 nonn
%O A348044 1,2
%A A348044 _Antti Karttunen_, Sep 27 2021