Search: id:A053781 Results 1-1 of 1 results found. %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 Search completed in 0.001 seconds