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 A069925 #32 Jun 02 2022 14:50:10
%S A069925 1,1,1,2,2,4,6,16,18,40,62,160,210,448,660,2048,2570,5184,9198,24672,
%T A069925 32508,76032,121574,344064,405000,1005888,1569780,4511520,6066336,
%U A069925 12672000,23091222,67004160,85342752,200422656,289531200,892477440
%N A069925 a(n) = phi(2^n+1)/(2*n).
%C A069925 Number of primitive self-reciprocal polynomials of degree 2*n over GF(2). - _Joerg Arndt_, Jul 04 2012
%H A069925 Amiram Eldar, <a href="/A069925/b069925.txt">Table of n, a(n) for n = 1..1090</a>
%H A069925 Joerg Arndt, <a href="http://www.jjj.de/fxt/#fxtbook">Matters Computational (The Fxtbook)</a>, section 40.8 "Self-reciprocal polynomials", pp. 846-848.
%H A069925 Helmut Meyn and Werner Götz, <a href="http://www.mat.univie.ac.at/~slc/wpapers/s42hirsch.html">Self-reciprocal Polynomials Over Finite Fields</a>, Séminaire Lotharingien de Combinatoire, B21d, pp. 82-90, 1989.
%F A069925 a(n) = phi(2^n+1)/(2*n).
%F A069925 a(n) = A053285(n)/(2*n). - _Amiram Eldar_, Jun 02 2022
%t A069925 Table[EulerPhi[2^n+1]/(2n),{n,50}] (* _Harvey P. Dale_, Nov 15 2011 *)
%o A069925 (PARI) a(n) = eulerphi(2^n+1)/(2*n); /* _Joerg Arndt_, Jul 04 2012 */
%Y A069925 Cf. A011260 (degree-n primitive polynomials).
%Y A069925 Cf. A000048 (degree-2*n irreducible self-reciprocal polynomials).
%Y A069925 Cf. A000010, A000051, A053285.
%K A069925 easy,nonn
%O A069925 1,4
%A A069925 _Benoit Cloitre_, Apr 25 2002