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 A094361 #15 May 09 2024 04:44:31 %S A094361 4,1,16,4,64,16,256,64,1024,256,4096,1024,16384,4096,65536,16384, %T A094361 262144,65536,1048576,262144,4194304,1048576,16777216,4194304, %U A094361 67108864,16777216,268435456,67108864,1073741824,268435456,4294967296,1073741824 %N A094361 Pair-reversal of 1,4,4,16,16... %H A094361 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (0,4). %F A094361 a(n) = k^(n/2)(1+k*sqrt(k)-(1-ksqrt(k))(-1)^n)/(2*sqrt(k)), the pair reversal of 1,k,k,k^2,k^2,k^3,k^3,... for k=4. %F A094361 G.f.: (4+x)/(1-4*x^2). %F A094361 a(n) = (9*2^n+7*(-2)^n)/4. %F A094361 Recurrence: a(n) = 4a(n-2), a(0)=4, a(1)=1. - _Ralf Stephan_, Jul 17 2013 %t A094361 LinearRecurrence[{0,4},{4,1},50] (* _Harvey P. Dale_, Apr 15 2017 *) %Y A094361 Cf. A076736. %K A094361 nonn,easy %O A094361 0,1 %A A094361 _Paul Barry_, Apr 26 2004