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