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 A032125 #30 Aug 22 2015 11:16:17
%S A032125 3,9,30,108,408,1584,6240,24768,98688,393984,1574400,6294528,25171968,
%T A032125 100675584,402677760,1610661888,6442549248,25770000384,103079608320,
%U A032125 412317646848,1649269014528,6597072912384,26388285358080,105553128849408
%N A032125 "BIK" (reversible, indistinct, unlabeled) transform of 3,3,3,3...
%C A032125 Number of solutions (x,y,z) to x+y+z = 2^n, x>=0, y>=0, z>=0, gcd(x,y,z)=1. - _Vladeta Jovovic_, Dec 22 2002
%H A032125 Harvey P. Dale, <a href="/A032125/b032125.txt">Table of n, a(n) for n = 1..1000</a>
%H A032125 C. G. Bower, <a href="/transforms2.html">Transforms (2)</a>
%H A032125 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (6,-8)
%F A032125 a(n) = 3*2^(n-2)*(2^(n-1)+1). - _Vladeta Jovovic_, Dec 22 2002
%F A032125 Binomial transform of A067771 (if the offset is changed to 0). - _Carl Najafi_, Sep 09 2011
%F A032125 G.f. -3*x*(-1+3*x) / ( (4*x-1)*(2*x-1) ). a(n)=3*A007582(n-1). - _R. J. Mathar_, Sep 11 2011
%F A032125 a(1)=3, a(2)=9, a(n) = 6*a(n-1)-8*a(n-2). [_Harvey P. Dale_, Jan 01 2012]
%F A032125 E.g.f.: (3/8)*(exp(4*x) + 2*exp(2*x) - 3). - _G. C. Greubel_, Aug 22 2015
%t A032125 Table[3*2^(n-2)(2^(n-1)+1),{n,30}] (* or *) LinearRecurrence[{6,-8},{3,9},30] (* _Harvey P. Dale_, Jan 01 2012 *)
%t A032125 RecurrenceTable[{a[0]== 3, a[1]== 9, a[n]== 6*a[n-1] - 8*a[n-2]}, a, {n,50}] (* _G. C. Greubel_, Aug 22 2015 *)
%Y A032125 a(n) = A048240(2^n).
%K A032125 nonn,easy
%O A032125 1,1
%A A032125 _Christian G. Bower_