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A094308 Row sums of A094307.

%I A094308 #27 May 20 2020 05:00:05
%S A094308 1,3,11,34,182,282,2034,4908,15564,20100,223620,251340,3295140,
%T A094308 3964380,4324740,9370200,160014120,180434520,3440508120,3673300680,
%U A094308 3906093240,4350515400,100294646760,105648875640,533598607080,585081577080
%N A094308 Row sums of A094307.
%H A094308 Alois P. Heinz, <a href="/A094308/b094308.txt">Table of n, a(n) for n = 1..700</a>
%F A094308 a(n) = A003418(n) * (n - Sum_{frac(log_p(n)) < log_p(2)} (1 - 1/p)). - _Charlie Neder_, Jun 13 2019
%p A094308 A094307 := proc(n,k) local a,i ; if n = 1 then RETURN(1) ; elif k > 1 and k < n then a := [seq(i,i=1..k-1),seq(i,i=k+1..n)] ; elif k = n then a := [seq(i,i=1..k-1)] ; else a := [seq(i,i=2..n)] ; fi ; ilcm(op(a)) ; end: A094308 := proc(n) local k ; add( A094307(n,k),k=1..n) ; end: for n from 1 to 40 do printf("%d, ",A094308(n)) ; od ; # _R. J. Mathar_, Apr 30 2007
%t A094308 T[n_, k_] := LCM @@ Which[n == 1, {1}, 1 < k < n, Join[Range[k - 1], Range[k + 1, n]], k == n, Range[k - 1], True, Range[2, n]];
%t A094308 a[n_] := Sum[T[n, k], {k, 1, n}];
%t A094308 Array[a, 30] (* _Jean-François Alcover_, May 20 2020 *)
%o A094308 (PARI) T(n, k) = lcm(setminus(vector(n, i, i), Set(k))); \\ A094307
%o A094308 a(n) = sum(k=1, n, T(n,k)); \\ _Michel Marcus_, May 20 2020
%Y A094308 Cf. A094307, A003418.
%Y A094308 Lower diagonal of A181853. - _Alois P. Heinz_, Jul 29 2013
%K A094308 nonn
%O A094308 1,2
%A A094308 _Amarnath Murthy_, Apr 29 2004
%E A094308 More terms from _R. J. Mathar_, Apr 30 2007