# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a192034 Showing 1-1 of 1 %I A192034 #13 Feb 24 2019 12:33:20 %S A192034 2,8,4,9,14,25,15,49,22,18,21,57,45,169,34,69,38,205,143,119,46,87, %T A192034 217,93,130,133,58,323,62,111,160,553,319,63,74,129,30,305,82,75,86, %U A192034 36,68,335,48,159,301,355,369,171,106,177 %N A192034 Least k such that (product of proper divisors of k) mod (sum of proper divisors of k) equals n. %C A192034 Greedy inverse of A191906. %e A192034 a(0)=2 because A007956(2) mod A001065(2) = 1 mod 1 = 0, and 2 is the smallest number for which this is the case; %e A192034 a(1)=8 because A007956(8) mod A001065(8) = 8 mod 7 = 1, and 8 is the smallest number for which this is the case; %e A192034 a(2)=4 because A007956(4) mod A001065(4) = 2 mod 3 = 2, and 4 is the smallest number for which this is the case. %p A192034 A192034 := proc(n) local k ; for k from 2 do if A191906(k) = n then return k ; end if; end do: end proc: # _R. J. Mathar_, Jul 01 2011 %t A192034 ds[n_]:=Module[{divs=Most[Divisors[n]]},Mod[Times@@divs,Total[divs]]]; Join[ {2},Transpose[Table[SelectFirst[Table[{n,ds[n]},{n,2,2000}],#[[2]] == i&],{i,60}]][[1]]] (* _Harvey P. Dale_, Apr 11 2015 *) %Y A192034 Cf. A001065, A007956, A191906. %K A192034 nonn %O A192034 0,1 %A A192034 _Juri-Stepan Gerasimov_, Jun 21 2011 %E A192034 Corrected by _R. J. Mathar_, Jul 01 2011 %E A192034 Example section corrected by _Jon E. Schoenfield_, Feb 24 2019 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE