%I A039835
%S A039835 1,10,493,3382,158905,1089154,51167077,350704366,16475640049,
%T A039835 112925716858,5305104928861,36361730124070,1708227311453353,
%U A039835 11708364174233842,550043889183050965,3770056902373173214
%N A039835 Indices of triangular numbers which are also heptagonal.
%H A039835 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               HeptagonalTriangularNumber.html">Link to a section of The World of 
               Mathematics.</a>
%F A039835 G.f.: (-2x^4-9x^3+161x^2+9x+1)/[(1-x)(1-18x+x^2)(1+18x+x^2)].
%F A039835 a(n+2)=322*a(n+1)-a(n)+160 a(n+1)=161*a(n)+80+36*(20*a(n)^2+20*a(n)+9)^0.5 
               - Richard Choulet (richardchoulet(AT)yahoo.fr), Sep 29 2007
%Y A039835 Cf. A046193, A046194.
%Y A039835 Cf. A046194 A046193.
%Y A039835 Sequence in context: A159533 A035320 A071096 this_sequence A127947 A095232 
               A042209
%Y A039835 Adjacent sequences: A039832 A039833 A039834 this_sequence A039836 A039837 
               A039838
%K A039835 nonn
%O A039835 1,2
%A A039835 Eric Weisstein (eric(AT)weisstein.com)