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 A152100 #17 Aug 24 2025 11:26:33
%S A152100 1,14,76,218,472,870,1444,2226,3248,4542,6140,8074,10376,13078,16212,
%T A152100 19810,23904,28526,33708,39482,45880,52934,60676,69138,78352,88350,
%U A152100 99164,110826,123368,136822,151220,166594,182976,200398,218892,238490
%N A152100 Expansion of g.f. 1 - 2*x*(-7 - 10*x + x^2)/(x - 1)^4.
%H A152100 Harvey P. Dale, <a href="/A152100/b152100.txt">Table of n, a(n) for n = 0..1000</a>
%H A152100 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F A152100 From _R. J. Mathar_, Sep 22 2009: (Start)
%F A152100 a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4), n > 4.
%F A152100 a(n) = 2*n*(8*n^2 + 12*n + 1)/3, n > 0. (End)
%F A152100 E.g.f.: 1 + 2*exp(x)*x*(21 + 36*x + 8*x^2)/3. - _Stefano Spezia_, Aug 24 2025
%t A152100 Join[{1},LinearRecurrence[{4,-6,4,-1},{14,76,218,472},40]] (* _Harvey P. Dale_, Aug 07 2012 *)
%Y A152100 Cf. A006071.
%K A152100 nonn,easy
%O A152100 0,2
%A A152100 _N. J. A. Sloane_, Sep 21 2009, based on email from _R. J. Mathar_, Mar 22 2009
%E A152100 More terms from _R. J. Mathar_, Sep 22 2009