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 A079282 #19 Sep 08 2022 08:45:08 %S A079282 1,3,9,24,61,149,354,823,1881,4240,9449,20857,45666,99291,214589, %T A079282 461336,987221,2103917,4467394,9454895,19951601,41989408,88155409, %U A079282 184670769,386072386,805624179,1678235829,3490492968,7249103581,15034563845 %N A079282 Diagonal sums of triangle A055249. %H A079282 Vincenzo Librandi, <a href="/A079282/b079282.txt">Table of n, a(n) for n = 0..1000</a> %H A079282 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (5,-7,0,4). %F A079282 a(n) = sum(sum((k+1)binomial(n-j, n-2j-k), k, 0, n-2j), j, 0, floor(n/2)) %F A079282 a(n) = (n-1)*2^n + F(n+3), with F(n) = A000045(n). - _Ralf Stephan_, May 09 2004 %F A079282 G.f.: (1-x)^2 / ((1-2*x)^2 * (1-x-x^2)). [_Joerg Arndt_, Aug 05 2013] %t A079282 Table[(n - 1) 2^n + Fibonacci[n + 3], {n, 0, 30}] (* _Vincenzo Librandi_, Aug 05 2013 *) %t A079282 LinearRecurrence[{5,-7,0,4},{1,3,9,24},30] (* _Harvey P. Dale_, May 29 2021 *) %o A079282 (Magma) [(n-1)*2^n + Fibonacci(n+3): n in [0..30]]; // _Vincenzo Librandi_, Aug 05 2013 %Y A079282 Cf. A055249. %K A079282 easy,nonn %O A079282 0,2 %A A079282 _Paul Barry_, Feb 08 2003