%I #16 Aug 19 2024 11:38:21
%S 3,4,16,61,1861,4979,90191,58981439,10024953661
%N Integers equal to the sum of divisors of their anti-divisors.
%C Tested up tp 2*10^10. - _Giovanni Resta_, Aug 19 2024
%e Anti-divisors of 1861 are 2, 3, 17, 51, 61, 73, 219, 1241 and
%e sum of sigmas = 3 + 4 + 18 + 72 + 62 + 74 + 296 + 1332 = 1861.
%Y Cf. A000203, A066417, A178029.
%K nonn,hard,more
%O 1,1
%A _Paolo P. Lava_, Aug 17 2024
%E a(8)-a(9) from _Giovanni Resta_, Aug 19 2024