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 A117475 #10 Apr 26 2021 14:37:32 %S A117475 37,65,205,373,1193,2173,6953,12665,40525,73817,236197,430237,1376657, %T A117475 2507605,8023745,14615393,46765813,85184753,272571133,496493125, %U A117475 1588660985,2893773997,9259394777,16866150857,53967707677,98303131145 %N A117475 The values of c in a^2 + b^2 = c^2 where b - a = 23 and gcd(a,b,c) = 1. %C A117475 b - a = 23 is the fourth term in A058529. The values of a are in A117476. %H A117475 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (0,6,0,-1). %F A117475 c(1)=37, c(2)=65, c(3)=205, c(4)=373, c(n) = 6*c(n-2) - c(n-4). %F A117475 G.f.: -x*(17*x^3+17*x^2-65*x-37) / ((x^2-2*x-1)*(x^2+2*x-1)). [_Colin Barker_, Dec 17 2012] %e A117475 c(5) = 6*205 - 37 = 1193 and 832^2 + 855^2 = 1193^2 and 855-832=23 and gcd(832,855,1193)=1. %Y A117475 Cf. A058529, A117476. %K A117475 nonn,easy %O A117475 1,1 %A A117475 Andras Erszegi (erszegi.andras(AT)chello.hu), Mar 19 2006