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%I #9 Jun 19 2019 08:57:44
%S 24,60,72,180,1440,2160,1872,2640,2400,3000,2880,3024,4320,4320,4320,
%T 5280,5280,7400,8640,10080,10200,11520,11880,11520,11088,12960,12096,
%U 14400,25920,21600,26640,34560,25200,40320,34560,36000,51840,60480,63360,60480,65280
%N Values of usigma(n) = usigma(n+1).
%C The sum of unitary divisors of numbers n such that n and n+1 have the same sum.
%C The unitary version of A053215.
%H Amiram Eldar, <a href="/A290303/b290303.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A034448(A064125(n)).
%t usigma[n_] := Block[{d = Divisors[n]}, Plus @@ Select[d, GCD[ #, n/# ] == 1 &]];a={}; u1=0; For[k=0, k<10^5, k++; u2=usigma[k]; If[u1==u2, a = AppendTo[a, u1]]; u1=u2]; a
%Y Cf. A002961, A034448, A053215, A064125.
%K nonn
%O 1,1
%A _Amiram Eldar_, Jul 26 2017