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 A129982 #15 Feb 26 2019 01:37:47
%S A129982 1,0,1,1,1,1,1,2,1,3,1,5,1,8,1,13,1,21,1,34,1,55,1,89,1,144,1,233,1,
%T A129982 377,1,610,1,987,1,1597,1,2584,1,4181,1,6765,1,10946,1,17711,1,28657,
%U A129982 1,46368,1,75025,1,121393,1,196418,1,317811,1,514229,1,832040,1,1346269,1
%N A129982 Fibonacci numbers sandwiched between 1's.
%C A129982 This sequence is similar to Somos-5 (A006721). - _Michael Somos_, Aug 15 2014
%H A129982 <a href="/index/Rec">Index entries for linear recurrences with constant coefficients</a>, signature (0,2,0,0,0,-1).
%F A129982 G.f.: (1 - x^2 + x^3 - x^4 - x^5) / (1 - 2*x^2 + x^6). - _Michael Somos_, Aug 15 2014
%F A129982 a(2-n) = (-1)^(mod(n, 4) == 1) * a(n) for all n in Z. - _Michael Somos_, Aug 15 2014
%F A129982 a(2*n) = 1, a(2*n + 1) = A000045(n) for all n in Z. - _Michael Somos_, Aug 15 2014
%F A129982 a(n) = 2*a(n-2) - a(n-6) for all n in Z. - _Michael Somos_, Aug 15 2014
%F A129982 0 = a(n)*a(n+5) - a(n+1)*a(n+4) - a(n+2)*a(n+3) for all even n in Z. - _Michael Somos_, Aug 15 2014
%F A129982 0 = a(n)*a(n+5) - a(n+1)*a(n+4) + a(n+2)*a(n+3) for all odd n in Z. - _Michael Somos_, Aug 15 2014
%e A129982 G.f. = 1 + x^2 + x^3 + x^4 + x^5 + x^6 + 2*x^7 + x^8 + 3*x^9 + x^10 + ...
%p A129982 G := 1/(1-x^2)+x^3/(1-x^2-x^4); Gser := series(G, x = 0, 70); seq(coeff(Gser, x, n), n = 0 .. 65); # _Emeric Deutsch_, Jul 09 2007
%t A129982 a[ n_] := If[ OddQ[n], Fibonacci[ Quotient[ n, 2]], 1]; (* _Michael Somos_, Aug 15 2014 *)
%o A129982 (PARI) {a(n) = if( n%2, fibonacci( n\2), 1)}; /* _Michael Somos_, Aug 15 2014 */
%Y A129982 Cf. A000045, A006721.
%K A129982 nonn,easy
%O A129982 0,8
%A A129982 _Paul Curtz_, Jun 14 2007
%E A129982 More terms from _Emeric Deutsch_, Jul 09 2007