login
Numbers n such that A049820(x) = n has a solution.
12

%I #19 Oct 14 2015 12:46:33

%S 0,1,2,3,4,5,6,9,10,11,12,14,15,16,17,18,21,22,23,26,27,29,30,31,32,

%T 34,35,38,39,41,42,44,45,46,47,48,51,53,54,57,58,59,60,61,62,65,69,70,

%U 71,72,73,76,77,78,80,81,82,83,84,86,87,89,90,91,92,93,94

%N Numbers n such that A049820(x) = n has a solution.

%C Complement of A045765.

%H Jaroslav Krizek, <a href="/A236562/b236562.txt">Table of n, a(n) for n = 1..10000</a>

%F A060990(a(n)) > 0.

%e 10 is in sequence because A049820(14) = 14 - A000005(14) = 14 - 4 = 10.

%t Take[Sort@ DeleteDuplicates@ Table[n - DivisorSigma[0, n], {n, 1200}], 67] (* _Michael De Vlieger_, Oct 13 2015 *)

%Y Cf. A049820, A236561, A236565.

%K nonn

%O 1,3

%A _Jaroslav Krizek_, Feb 09 2014