%I #14 Mar 14 2024 03:44:27
%S 123,285,734,1437,2733,926875,2122173,21466939,797141342
%N Deficient numbers k such that k-s(k)-s(k-s(k)) = s(s(k))-s(k) or s(k-s(k))-k+s(k) = s(k)-s(s(k)).
%C Here s(k) = sigma(k) - k (see A001065).
%C a(10) > 10^10, if it exists. - _Amiram Eldar_, Mar 14 2024
%o (PARI) s(n) = sigma(n) - n;
%o is(n) = {my(s1 = s(n)); if(s1 >= n, 0, n - s1 - s(n-s1) == s(s1) - s1);} \\ _Amiram Eldar_, Mar 14 2024
%Y Cf. A001065, A005100.
%K nonn,more
%O 1,1
%A _Naohiro Nomoto_
%E More terms from _Jason Earls_, Aug 30 2001
%E Offset corrected, wrong term removed and a(8)-a(9) added by _Amiram Eldar_, Mar 14 2024
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