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 A141531 #37 Feb 15 2021 07:00:31 %S A141531 1,1,1,-2,4,-8,16,-32,64,-128,256,-512,1024,-2048,4096,-8192,16384, %T A141531 -32768,65536,-131072,262144,-524288,1048576,-2097152,4194304, %U A141531 -8388608,16777216,-33554432,67108864,-134217728,268435456,-536870912,1073741824,-2147483648 %N A141531 Inverse binomial transform of A001651. %H A141531 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (-2). %F A141531 a(n) = A123344(n+1), n > 0. %F A141531 a(n) = (-2)^n/4 = (-1)^n*A000079(n-2), n > 1. %F A141531 O.g.f.: (1 + 3*x + 3*x^2)/(1 + 2*x). - _R. J. Mathar_, Aug 27 2008 %F A141531 a(n) = -2*a(n-1) for n >= 3; a(0)=1, a(1)=1, a(2)=1. - _Harvey P. Dale_, May 04 2012 %F A141531 G.f.: x+1/Q(0) where Q(k) = 1 + x*(k+1)/(1 - 1/(1 - (k+1)/Q(k+1))); (continued fraction). - _Sergei N. Gladkovskii_, Sep 23 2012 %F A141531 G.f.: 1+x/U(0) where U(k) = 1 - x*(k+4) + x*(k+3)/U(k+1); (continued fraction). - _Sergei N. Gladkovskii_, Oct 11 2012 %F A141531 a(n) = A122803(n-2) for n >= 2. - _Georg Fischer_, Nov 03 2018 %F A141531 E.g.f.: (3/4) + (3/2)*x + (1/4)*exp(-2*x). - _Alejandro J. Becerra Jr._, Feb 15 2021 %t A141531 CoefficientList[Series[(1+3x+3x^2)/(1+2x),{x,0,40}],x] (* or *) Join[ {1,1},NestList[-2#&,1,38]] (* _Harvey P. Dale_, May 04 2012 *) %t A141531 Join[{1, 1},LinearRecurrence[{-2},{1},32]] (* _Ray Chandler_, Aug 12 2015 *) %o A141531 (PARI) Vec((1 + 3*x + 3*x^2)/(1 + 2*x) + O(x^40)) \\ _Andrew Howroyd_, Nov 03 2018 %Y A141531 Cf. A000079, A122803, A123344. %K A141531 sign %O A141531 0,4 %A A141531 _Paul Curtz_, Aug 12 2008 %E A141531 Edited and extended by _R. J. Mathar_, Aug 28 2008