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 A084264 #17 Aug 28 2025 06:33:10
%S A084264 1,2,7,22,64,176,464,1184,2944,7168,17152,40448,94208,217088,495616,
%T A084264 1122304,2523136,5636096,12517376,27656192,60817408,133169152,
%U A084264 290455552,631242752,1367343104,2952790016,6358564864,13656653824,29259464704
%N A084264 Binomial transform of A084263.
%C A084264 Also the number of matchings in the (n-1)-book graph. - _Eric W. Weisstein_, Sep 30 2017
%H A084264 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/BookGraph.html">Book Graph</a>
%H A084264 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/IndependentEdgeSet.html">Independent Edge Set</a>
%H A084264 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Matching.html">Matching</a>
%H A084264 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (6,-12,8)
%F A084264 E.g.f.: exp(x)*cosh(x)+exp(2*x)*(x+x^2/2).
%F A084264 O.g.f.: (1-x)*(1-3*x+4*x^2)/(1-2*x)^3. - _R. J. Mathar_, Apr 02 2008
%F A084264 a(0)=1, a(1)=2, a(2)=7, a(3)=22, a(n) = 6*a(n-1)-12*a(n-2)+8*a(n-3). - _Harvey P. Dale_, Mar 25 2012
%F A084264 a(n) = 2^(n-3)*(n^2+3*n+4) for n > 0. - _Eric W. Weisstein_, Sep 30 2017
%t A084264 CoefficientList[Series[(-1 + x)(1 - 3 x + 4 x^2)/(-1 + 2 x)^3, {x, 0, 30}], x]
%t A084264 Join[{1}, LinearRecurrence[{6, -12, 8}, {2, 7, 22}, 30]]
%t A084264 Table[If[n == 0, 1, 2^(n - 3) (n^2 + 3 n + 4)], {n, 0, 20}] (* _Eric W. Weisstein_, Sep 30 2017 *)
%Y A084264 Cf. A084263.
%K A084264 easy,nonn,changed
%O A084264 0,2
%A A084264 _Paul Barry_, May 31 2003