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 A120079 #8 Apr 27 2023 17:03:55 %S A120079 1,7,68,279,7056,7100,349200,1400175,12622400,12637296,1530446400, %T A120079 1531460700,258950260800,259056111600,259141506624,1036845584775, %U A120079 299715332716800,299771444772800,108234634597689600,108249271042728816,108261866776377600,108272784263716800 %N A120079 Unsigned row sums of triangle A120078. %H A120079 G. C. Greubel, <a href="/A120079/b120079.txt">Table of n, a(n) for n = 1..1000</a> %F A120079 a(n) = Sum_{k=1..n} abs(A120078(n,k)), n >= 1. %F A120079 From _G. C. Greubel_, Apr 26 2023: (Start) %F A120079 a(n) = (2 - 1/n^2)*A051418(n). %F A120079 a(n) = A056220(n)*A051418(n)/A000290(n). (End) %t A120079 Table[(2-1/n^2)*(Apply[LCM, Range[n]])^2, {n, 40}] (* _G. C. Greubel_, Apr 26 2023 *) %o A120079 (Magma) [(2-1/n^2)*(Lcm([1..n]))^2: n in [1..40]]; // _G. C. Greubel_, Apr 26 2023 %o A120079 (SageMath) %o A120079 def A120079(n): return (2 - 1/n^2)*(lcm(range(1, n+1)))^2 %o A120079 [A120079(n) for n in range(1,41)] # _G. C. Greubel_, Apr 26 2023 %Y A120079 Signed row sums conjectured to be A027451(n), which also appears in the denominator of o.g.f.s. G(x, n) given in A120078 as numbers A(n). %Y A120079 Cf. A000290, A051418, A056220. %K A120079 nonn,easy %O A120079 1,2 %A A120079 _Wolfdieter Lang_, Jul 20 2006 %E A120079 Terms a(11) onward added by _G. C. Greubel_, Apr 26 2023