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 A014477 #52 Dec 12 2022 18:30:33 %S A014477 1,8,36,128,400,1152,3136,8192,20736,51200,123904,294912,692224, %T A014477 1605632,3686400,8388608,18939904,42467328,94633984,209715200, %U A014477 462422016,1015021568,2218786816,4831838208,10485760000,22682796032,48922361856,105226698752,225754218496 %N A014477 Expansion of (1 + 2*x)/(1 - 2*x)^3. %C A014477 The sequence 0,1,8,... has a(n) = n^2*2^(n-1) and is the binomial transform of the hexagonal numbers A000384 (with leading 0). - _Paul Barry_, Jun 09 2003 %C A014477 As 0,1,8,... this is n^2*2^(n-1), the binomial transform of the hexagonal numbers A000384 (include the leading 0). Partial sums are A036826. - _Paul Barry_, Jun 10 2003 %C A014477 Sequence gives total value of all possible sums of distinct odd integers with maximum term less than 2n+1. E.g., for a(3) we can have the sums 1, 3, 5, 1+3, 1+5, 3+5, 1+3+5, which sum to 1+3+5+4+6+8+9 = 36. - _Jon Perry_, Feb 06 2004 %C A014477 Number of edges on a partially truncated (n+1)-cube (column 2 of A271316). %H A014477 Vincenzo Librandi, <a href="/A014477/b014477.txt">Table of n, a(n) for n = 0..1000</a> %H A014477 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (6,-12,8). %F A014477 O.g.f.: (1 + 2*x)/(1 - 2*x)^3 (see the name). %F A014477 a(n) = (n+1)^2*2^n = A007758(n+1)/2. - _Henry Bottomley_, Jun 13 2001 %F A014477 The binomial transform of 0, 1, 8, ... is A077616. - _Paul Barry_, Jul 24 2003 %F A014477 a(1)=1, a(n) = 2a(n-1) + (2n-1)*2^(n-1). - _Jon Perry_, Feb 06 2004 %F A014477 a(n) = sum of (n+1)-th row of the triangle in A118416. - _Reinhard Zumkeller_, Apr 27 2006 %F A014477 a(n) = Sum_{j=0..n} binomial(n,j)*n*j. - _Zerinvary Lajos_, Oct 19 2006 %F A014477 E.g.f.: exp(2*x)*(1 + 6*x + 8*x^2/2!). - _Wolfdieter Lang_, Jul 29 2017 %F A014477 Sum_{n>=0} 1/a(n) = Pi^2/6 - log(2)^2. - _Daniel Suteu_, Oct 31 2017 %F A014477 Sum_{n>=0} (-1)^n/a(n) = -2 * Li_2(-1/2) = -2 * A355234. - _Amiram Eldar_, Oct 01 2022 %p A014477 a:=n->sum(binomial(n,j)*n*j,j=0..n): seq(a(n), n=0..25); # _Zerinvary Lajos_, Oct 19 2006 %p A014477 a:=n->sum(n*numbcomb(n)/2, j=1..n): seq(a(n), n=1..25); # _Zerinvary Lajos_, Apr 25 2007 %t A014477 f[n_]:=(n^2*2^n)/2;Table[f[n],{n,0,5!}] (* _Vladimir Joseph Stephan Orlovsky_, Dec 05 2009 *) %o A014477 (Magma) [(n+1)^2*2^n: n in [0..35]]; // _Vincenzo Librandi_, Aug 21 2011 %o A014477 (PARI) a(n)=(n+1)^2*2^n \\ _Charles R Greathouse IV_, Apr 07 2016 %Y A014477 Cf. A007758, A036826, A118414, A355234. %K A014477 nonn,easy %O A014477 0,2 %A A014477 _N. J. A. Sloane_