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a(n) = smallest number k such that k - ms(k) = n, or 0 if no such number has been found, where ms(k) = sum of divisors of k other than k.
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%I #8 Nov 07 2016 14:14:01

%S 6,1,3,0,5,9,7,50,22,0,11,244036,13,0,27,0,17,0,19,25,46,0,23,0,124,

%T 98,58,0,29,0,31,0,250,0,57,0,37,484,55,0,41,49,43,0,94,0,47,225,1264,

%U 0,106,0,53,0,87,0,118,0,59,0,61,2888,85,0,134,0,67,0,142,0,71,676,73,0

%N a(n) = smallest number k such that k - ms(k) = n, or 0 if no such number has been found, where ms(k) = sum of divisors of k other than k.

%H F. Firoozbakht, M. F. Hasler, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL13/Hasler/hasler2.html">Variations on Euclid's formula for Perfect Numbers</a>, JIS 13 (2010) #10.3.1

%e a(5) = 9 because the first 5 in A033879 is A033879(9).

%Y Cf. A082731.

%Y Cf. A001065, A033879.

%K nonn

%O 0,1

%A _Amarnath Murthy_, Apr 14 2003

%E More terms from _David Wasserman_, Sep 29 2004, who remarks that he searched up to 10^16.