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 A082308 #10 Sep 08 2022 08:45:10 %S A082308 1,5,25,127,657,3449,18281,97395,519841,2773741,14776377,78538343, %T A082308 416367665,2201517153,11610231433,61078202971,320570884929, %U A082308 1678897264085,8775159682649,45780628812879,238431945108433 %N A082308 Expansion of e.g.f. (1+x)*exp(4*x)*cosh(x). %C A082308 Binomial transform of A082307. %H A082308 G. C. Greubel, <a href="/A082308/b082308.txt">Table of n, a(n) for n = 0..1000</a> %H A082308 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (16,-94,240,-225). %F A082308 a(n) = (A081105(n) + A006234(n))/2. %F A082308 a(n) = ((n+3)*3^(n-1) + (n+5)*5^(n-1))/2. %F A082308 G.f.: ((1-4*x)/(1-5*x)^2 + (1-2*x)/(1-3*x)^2)/2. %F A082308 E.g.f.: (1+x)*exp(4*x)*cosh(x) = (1+x)*(exp(5*x) + exp(3*x))/2. %t A082308 With[{nmax = 50}, CoefficientList[Series[(1 + x)*Exp[4*x]*Cosh[x], {x, 0, nmax}], x]*Range[0, nmax]!] (* _G. C. Greubel_, Sep 16 2018 *) %o A082308 (PARI) x='x+O('x^30); Vec(serlaplace((1+x)*exp(4*x)*cosh(x))) \\ _G. C. Greubel_, Sep 16 2018 %o A082308 (Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!((1+x)*Exp(4*x)*Cosh(x))); [Factorial(n-1)*b[n]: n in [1..m]]; // _G. C. Greubel_, Sep 16 2018 %Y A082308 Cf. A082309. %K A082308 easy,nonn %O A082308 0,2 %A A082308 _Paul Barry_, Apr 09 2003