%I A062717
%S A062717 0,4,8,20,28,48,60,88,104,140,160,204,228,280,308,368,400,468,504,580,
%T A062717 620,704,748,840,888,988,1040,1148,1204,1320,1380,1504,1568,1700,1768,
%U A062717 1908,1980,2128,2204,2360,2440,2604,2688,2860,2948,3128,3220,3408,3504
%N A062717 Numbers n such that 6n+1 is a perfect square.
%C A062717 Sequence allows us to find X values of the equation: 6*X^3 + X^2 = Y^2. 
               - Mohamed Bouhamida (bhmd95(AT)yahoo.fr), Nov 06 2007
%C A062717 Averages of the Triangular numbers which take integer values. [From Vladimir 
               Orlovsky (4vladimir(AT)gmail.com), Aug 05 2009]
%H A062717 Harry J. Smith, <a href="b062717.txt">Table of n, a(n) for n=1,...,1000</
               a>
%F A062717 G.f.: (4x^3+4x^2+4x)/[(1-x)(1-x^2)^2].
%F A062717 a(2n)=n(6n+2), a(2n+1)=6*n^2+10n+4. - Mohamed Bouhamida (bhmd95(AT)yahoo.fr), 
               Nov 06 2007
%t A062717 a=b=0;lst={};Do[b=(a+=n*(n-1)/2)/n;If[b==IntegerPart[b],AppendTo[lst,
               b]],{n,6!}];lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), 
               Aug 05 2009]
%o A062717 (PARI) je=[]; for(n=0,7000, if(issquare(6*n+1),je=concat(je,n))); je
%o A062717 (PARI) { n=0; for (m=0, 10^9, if (issquare(6*m + 1), write("b062717.txt", 
               n++, " ", m); if (n==1000, break)) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), 
               Aug 09 2009]
%Y A062717 Equals 4 * A001318.
%Y A062717 Cf. A005563, A046092, A001082, A002378, A036666.
%Y A062717 Cf. A160757, A000217 [From Vladimir Orlovsky (4vladimir(AT)gmail.com), 
               Aug 05 2009]
%Y A062717 Sequence in context: A061814 A087254 A160726 this_sequence A084922 A047185 
               A034733
%Y A062717 Adjacent sequences: A062714 A062715 A062716 this_sequence A062718 A062719 
               A062720
%K A062717 easy,nonn
%O A062717 1,2
%A A062717 Jason Earls (zevi_35711(AT)yahoo.com), Jul 14 2001