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%I #17 Jun 17 2024 07:23:24
%S 2,9,30,38,285,339,2912,6684,22635,25145,304854,332562,4684589,
%T 5044935,5405280,11531384,208287927,220540149,4423058450,4655850990,
%U 4888643529,5121436067,123147263964,128501492820,669278609675,696049754049,2168462696022,2248776129194
%N Sum of n-th row of triangle in A079784.
%F a(n) = n*[A079782(n)-(n-1)/2]. - _R. J. Mathar_, Nov 12 2006
%e The fifth row 55,56,57,58,59 is divisible by 5,4,3,2 and 1 respectively.
%t a[n_] := n*(Which[n == 1, 2, n == 2, 5, n == 3, 11, True, LCM @@ Range[n] - 1] - (n-1)/2);
%t Table[a[n], {n, 1, 30}] (* _Jean-François Alcover_, Jun 17 2024 *)
%o (PARI) okrow(m, n) = {v = vector(n, i, i+m-1); for (i=1, n, if (v[i] % (n-i+1), return (0));); return (1);}
%o a(n) = {m = n+1; while (! okrow(m, n), m++); sum(k=1, n, m+k-1);} \\ _Michel Marcus_, Feb 28 2014
%Y Cf. A079781, A079782, A079784.
%K nonn
%O 1,1
%A _Amarnath Murthy_, Feb 03 2003
%E More terms from _Michel Marcus_, Feb 28 2014