%I A053781
%S A053781 1,2,3,7,11,71,107,115,139,155,681,1671,4876,21464,30046,311271,788749,
%T A053781 10893662,20743270,134568163,163879554,920161004,6364787032,21400458779,
%U A053781 47934932406,56133884369
%N A053781 Numbers n such that n divides sum of first n composite numbers.
%F A053781 When n | A053767(n). - Robert G. Wilson v (rgwv(AT)rgwv.com), Nov 24 
               2004
%t A053781 c = s = 0; Do[ If[ !PrimeQ[n], c++; s = s + n; If[ Mod[s, c] == 0, Print[c]]], 
               {n, 2, 10^9}] (from Robert G. Wilson v Nov 23 2004)
%Y A053781 Cf. A002808.
%Y A053781 Sequence in context: A056292 A106125 A073609 this_sequence A066749 A046480 
               A137767
%Y A053781 Adjacent sequences: A053778 A053779 A053780 this_sequence A053782 A053783 
               A053784
%K A053781 more,nonn
%O A053781 1,2
%A A053781 G. L. Honaker, Jr. (honak3r(AT)gmail.com), Mar 29 2000
%E A053781 a(19), a(20), a(21) & a(22) from Robert G. Wilson v (rgwv(AT)rgwv.com), 
               Nov 24 2004
%E A053781 a(23), a(24), a(25) & a(26) from Sean A. Irvine (sairvin(AT)xtra.co.nz), 
               Oct 01 2009