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 A026848 #13 Sep 08 2022 08:44:49 %S A026848 1,11,79,471,2535,12809,62067,292085,1345718,6102780,27343148, %T A026848 121359692,534632836,2341151646,10201950700,44278673806,191540714294, %U A026848 826265471868,3555992623850,15273547250820,65491352071266,280412963707416 %N A026848 a(n) = T(2n,n-4), T given by A026736. %C A026848 Is this the same as A026841? - _R. J. Mathar_, Oct 23 2008 %C A026848 Column k=10 of triangle A236830. - _Philippe Deléham_, Feb 02 2014 %H A026848 G. C. Greubel, <a href="/A026848/b026848.txt">Table of n, a(n) for n = 4..1000</a> %F A026848 a(n) = A026841(n). - _Philippe Deléham_, Feb 02 2014 %F A026848 G.f.: (x^4*C(x)^10)/(1-x*C(x)^3) where C(x) is the g.f. of A000108. - _Philippe Deléham_, Feb 02 2014 %t A026848 Drop[CoefficientList[Series[(1-Sqrt[1-4*x])^10/(128*x^4*(8*x^2 -(1 - Sqrt[1-4*x])^3 )), {x,0,40}], x], 4] (* _G. C. Greubel_, Jul 17 2019 *) %o A026848 (PARI) my(x='x+O('x^40)); Vec((1-sqrt(1-4*x))^10/(128*x^4*(8*x^2 -(1 - sqrt(1-4*x))^3 ))) \\ _G. C. Greubel_, Jul 17 2019 %o A026848 (Magma) R<x>:=PowerSeriesRing(Rationals(), 40); Coefficients(R!( (1-Sqrt(1-4*x))^10/(128*x^4*(8*x^2 -(1-Sqrt(1-4*x))^3 )) )); // _G. C. Greubel_, Jul 17 2019 %o A026848 (Sage) a=((1-sqrt(1-4*x))^10/(128*x^4*(8*x^2 -(1-sqrt(1-4*x))^3 ))).series(x, 45).coefficients(x, sparse=False); a[4:40] # _G. C. Greubel_, Jul 17 2019 %Y A026848 Cf. A236830. %K A026848 nonn %O A026848 4,2 %A A026848 _Clark Kimberling_