%I A046191
%S A046191 1,77,7521,736957,72214241,7076258637,693401132161,67946234693117,
%T A046191 6658037598793281,652419738447048397,63930476330211949601,
%U A046191 6264534260622324012477,613860427064657541273121
%N A046191 Indices of hexagonal numbers which are also octagonal.
%H A046191 Herman Jamke (hermanjamke(AT)fastmail.fm), Apr 19 2008, <a href="b046191.txt">
               Table of n, a(n) for n = 1..20</a>
%H A046191 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               OctagonalHexagonalNumber.html">Link to a section of The World of 
               Mathematics.</a>
%p A046191 a:=5+2*sqrt(6): b:=5-2*sqrt(6): s:=n->a^n+b^n: d:=n->sqrt(6)*(a^n-b^n):for 
               n from 0 to 40 do x:=simplify(s(n)-1/4*d(n)): y:=simplify(1/3*d(n)-s(n)/
               2): if(type((1+x/2)/3,integer) and type((1+y)/4,integer)) then printf("%d, 
               ",(1+y)/4) fi: x:=simplify(s(n+1)+1/4*d(n+1)): y:=simplify(1/3*d(n+1)+s(n+1)/
               2): if(type((1+x/2)/3,integer) and type((1+y)/4,integer)) then printf("%d, 
               ",(1+y)/4) fi: od: - Herman Jamke (hermanjamke(AT)fastmail.fm), Apr 
               19 2008
%Y A046191 Cf. A046190, A046192.
%Y A046191 Sequence in context: A116319 A107787 A099638 this_sequence A115616 A120799 
               A098024
%Y A046191 Adjacent sequences: A046188 A046189 A046190 this_sequence A046192 A046193 
               A046194
%K A046191 nonn
%O A046191 1,2
%A A046191 Eric Weisstein (eric(AT)weisstein.com)
%E A046191 1 more term from Larry Reeves (larryr(AT)acm.org), May 07 2001
%E A046191 One more term from Lior Manor (lior.manor(AT)gmail.com) Feb 13 2002
%E A046191 More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Apr 19 2008