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%I #5 Apr 12 2020 08:45:30
%S 14,16101,72926,97101,2872701,7610324
%N Numbers k such that A330575(k) = A330575(k+1).
%C a(7) > 6*10*8.
%H Thomas Fink, <a href="https://arxiv.org/abs/1912.07979">Recursively divisible numbers</a>, arXiv:1912.07979 [math.NT], 2019.
%e 14 is a term since A330575(14) = A330575(15) = 26.
%t s[1] = 1; s[n_] := s[n] = n + DivisorSum[n, s[#] &, # < n &]; seq = {}; s1 = s[1]; Do[s2 = s[n]; If[s1 == s2, AppendTo[seq, n-1]]; s1 = s2, {n, 2, 10^5}]; seq
%Y Cf. A330575.
%Y Similar sequences: A002961, A064115, A064125, A293183, A306985.
%K nonn,more
%O 1,1
%A _Amiram Eldar_, Apr 11 2020
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