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 A058966 #20 Dec 21 2024 23:51:11
%S A058966 1,2,10,30,78,190,446,1022,2302,5118,11262,24574,53246,114686,245758,
%T A058966 524286,1114110,2359294,4980734,10485758,22020094,46137342,96468990,
%U A058966 201326590,419430398,872415230,1811939326,3758096382,7784628222,16106127358,33285996542,68719476734
%N A058966 a(3) = 1, otherwise a(n) = n*2^(n-3) - 2^(n-2) - 2.
%D A058966 B. Elspas, The theory of multirail cascades, in A. Mukhopadhyay, ed., Recent Developments in Switching Theory, Ac. Press, 1971, Chap. 8, see esp. p. 361 (S_1(n)).
%H A058966 Harry J. Smith, <a href="/A058966/b058966.txt">Table of n, a(n) for n = 3...200</a>
%H A058966 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (5,-8,4).
%F A058966 From _Colin Barker_, Mar 23 2012: (Start)
%F A058966 a(n) = 5*a(n-1)-8*a(n-2)+4*a(n-3) for n>6.
%F A058966 G.f.: x^3*(1-3*x+8*x^2-8*x^3)/((1-x)*(1-2*x)^2). (End)
%t A058966 Join[{1},Table[n*2^(n-3)-2^(n-2)-2,{n,4,40}]] (* or *) LinearRecurrence[ {5,-8,4},{1,2,10,30},40] (* _Harvey P. Dale_, Dec 22 2019 *)
%o A058966 (PARI) a(n) = { abs(n*2^(n-3)-2^(n-2)-2) } \\ _Harry J. Smith_, Jun 24 2009
%K A058966 nonn,easy
%O A058966 3,2
%A A058966 _N. J. A. Sloane_, Jan 14 2001