%I A046190
%S A046190 1,63,6141,601723,58962681,5777740983,566159653621,55477868313843,
%T A046190 5436264935102961,532698485771776303,52199015340698974701,
%U A046190 5114970804902727744363,501214939865126619972841
%N A046190 Indices of octagonal numbers which are also hexagonal numbers.
%H A046190 Herman Jamke (hermanjamke(AT)fastmail.fm), Apr 19 2008, <a href="b046190.txt">
Table of n, a(n) for n = 1..20</a>
%H A046190 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 A046190 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+x/2)/3) 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+x/2)/3) fi: od: - Herman Jamke (hermanjamke(AT)fastmail.fm),
Apr 19 2008
%Y A046190 Cf. A046191, A046192.
%Y A046190 Sequence in context: A069381 A051589 A069407 this_sequence A093263 A069433
A062208
%Y A046190 Adjacent sequences: A046187 A046188 A046189 this_sequence A046191 A046192
A046193
%K A046190 nonn
%O A046190 1,2
%A A046190 Eric Weisstein (eric(AT)weisstein.com)
%E A046190 More terms from Larry Reeves (larryr(AT)acm.org), May 07 2001
%E A046190 One more term from Lior Manor (lior.manor(AT)gmail.com) Feb 13 2002
%E A046190 More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Apr 19 2008
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