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 A022276 #37 Sep 08 2022 08:44:46 %S A022276 0,9,37,84,150,235,339,462,604,765,945,1144,1362,1599,1855,2130,2424, %T A022276 2737,3069,3420,3790,4179,4587,5014,5460,5925,6409,6912,7434,7975, %U A022276 8535,9114,9712,10329,10965,11620,12294,12987,13699,14430,15180,15949,16737,17544,18370 %N A022276 a(n) = n*(19*n - 1)/2. %H A022276 G. C. Greubel, <a href="/A022276/b022276.txt">Table of n, a(n) for n = 0..5000</a> %H A022276 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1). %F A022276 a(n) = 19*n + a(n-1) - 10 for n>0, a(0)=0. - _Vincenzo Librandi_, Aug 04 2010 %F A022276 From _Vincenzo Librandi_, Mar 31 2015: (Start) %F A022276 G.f.: x*(9 + 10*x)/(1 - x)^3. %F A022276 a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>2. (End) %F A022276 a(n) = A022277(-n). - _Bruno Berselli_, Apr 01 2015 %F A022276 a(n) = A000217(10*n-1) - A000217(9*n-1). - _Bruno Berselli_, Oct 17 2016 %F A022276 E.g.f.: (x/2)*(19*x + 18)*exp(x). - _G. C. Greubel_, Aug 23 2017 %t A022276 Table[n (19 n - 1)/2, {n, 0, 40}] (* _Bruno Berselli_, Mar 12 2015 *) %t A022276 CoefficientList[Series[x (9 + 10 x) / (1 - x)^3, {x, 0, 40}], x] (* _Vincenzo Librandi_, Mar 31 2015 *) %t A022276 LinearRecurrence[{3,-3,1},{0,9,37},50] (* _Harvey P. Dale_, Jul 25 2021 *) %o A022276 (Magma) [n*(19*n - 1)/2: n in [0..45]]; // _Vincenzo Librandi_, Mar 31 2015 %o A022276 (PARI) a(n)=n*(19*n-1)/2 \\ _Charles R Greathouse IV_, Jun 17 2017 %Y A022276 Cf. A000217, A022277. %Y A022276 Cf. similar sequences listed in A022288. %K A022276 nonn,easy %O A022276 0,2 %A A022276 _N. J. A. Sloane_ %E A022276 More terms from _Vincenzo Librandi_, Mar 31 2015