This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A341929 #50 Mar 25 2021 05:13:51 %S A341929 1,2,15,118,929,7314,57583,453350,3569217,28100386,221233871, %T A341929 1741770582,13712930785,107961675698,849980474799,6691882122694, %U A341929 52685076506753,414788729931330,3265624762943887,25710209373619766,202416050226014241,1593618192434494162,12546529489249939055,98778617721565018278 %N A341929 Bisection of the numerators of the convergents of cf (1,1,6,1,6,1,...,6,1). %C A341929 15*a(n)^2 - 11 is a square for all terms. %C A341929 x = a(n) and y = a(n+1) satisfy the equation x^2 + y^2 - 8*x*y = -11. %C A341929 x = a(n) and y = a(n+2) satisfy x^2 + y^2 - 62*x*y = -704. %H A341929 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (8,-1). %F A341929 a(n) = 8*a(n-1) - a(n-2) for n >= 2. %F A341929 a(n) = A237262(2*n) for n >= 1. %F A341929 G.f.: (1 - 6*x)/(1 - 8*x + x^2). - _Stefano Spezia_, Mar 01 2021 %e A341929 a(3) = 8*15 - 2 = 118. %t A341929 LinearRecurrence [{8, -1}, {1,2}, 15] %o A341929 (PARI) my(p=Mod('x,'x^2-8*'x+1)); a(n) = subst(lift(p^n),'x,2); \\ _Kevin Ryde_, Feb 27 2021 %Y A341929 After a(0), bisection of A237262. %Y A341929 Cf. A341927. %K A341929 nonn,easy %O A341929 0,2 %A A341929 _John O. Oladokun_, Feb 23 2021