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 A118415 #16 Sep 16 2022 20:45:15
%S A118415 1,10,36,104,272,672,1600,3712,8448,18944,41984,92160,200704,434176,
%T A118415 933888,1998848,4259840,9043968,19136512,40370176,84934656,178257920,
%U A118415 373293056,780140544,1627389952,3388997632,7046430720,14629732352,30333206528,62813896704
%N A118415 a(n) = (4*n - 3) * 2^(n - 1).
%C A118415 Central terms of the triangle in A118413.
%H A118415 Vincenzo Librandi, <a href="/A118415/b118415.txt">Table of n, a(n) for n = 1..1000</a>
%H A118415 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (4,-4).
%F A118415 a(n) = A016813(n-1)*A000079(n-1).
%F A118415 O.g.f.: x*(1+6*x)/(-1+2*x)^2 . - _R. J. Mathar_, Feb 26 2008
%t A118415 CoefficientList[Series[(1 + 6 x)/(-1 + 2 x)^2, {x, 0, 40}], x] (* _Vincenzo Librandi_, May 21 2014 *)
%t A118415 LinearRecurrence[{4,-4},{1,10},30] (* _Harvey P. Dale_, Sep 16 2022 *)
%o A118415 (Magma)[(4*n-3)*2^(n-1): n in [1..40]]; // _Vincenzo Librandi_, Dec 26 2010
%Y A118415 Cf. A058962.
%K A118415 nonn,easy
%O A118415 1,2
%A A118415 _Reinhard Zumkeller_, Apr 27 2006
%E A118415 More terms from _R. J. Mathar_, Feb 26 2008