%I #9 Sep 28 2022 03:53:22
%S 4,9,8,15,14,21,121,289,529,46,28,841,62,24,1369,217,2209,106,68,3481,
%T 54,4489,134,5041,66,6241,158,6889,166,116,9409,10201,218,226,148,130,
%U 114,16129,17161,18769,278,90,24649,314,26569,27889,108,29929,225,32041,244
%N a(n) is the unique number m such that A001065(m) = A057709(n).
%H Amiram Eldar, <a href="/A357313/b357313.txt">Table of n, a(n) for n = 1..10000</a>
%F A001065(a(n)) = A057709(n).
%e a(1) = 4 since 4 is the unique solution m to A001065(m) = A057709(1) = 3.
%t seq[max_] := Module[{s = t = Table[0, {n, 1, max}], i, j}, Do[If[(i = DivisorSigma[1, n] - n) <= max, s[[i]]++; t[[i]] = n], {n, 2, (max - 1)^2}]; j = Position[s, 1] // Flatten; t[[j]]]; seq[250]
%Y Cf. A001065, A057709.
%K nonn
%O 1,1
%A _Amiram Eldar_, Sep 23 2022
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