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%I #17 Jun 06 2023 04:19:55
%S 1,2,4,3,6,6,4,8,8,12,5,10,10,15,10,6,12,12,18,12,24,7,14,14,21,14,28,
%T 14,8,16,16,24,16,32,16,32,9,18,18,27,18,36,18,36,27,10,20,20,30,20,
%U 40,20,40,30,40,11,22,22,33,22,44,22,44,33,44,22
%N Triangle read by rows: A127648 * A000012 * A130209.
%C Row sums = A143274: (1, 6, 15, 32, 50, 84, ...).
%F T(n,k) = n*d(k).
%e First few rows of the triangle =
%e 1;
%e 2, 4;
%e 3, 6, 6;
%e 4, 8, 8, 12;
%e 5, 10, 10, 15, 10;
%e 6, 12, 12, 18, 12, 24;
%e 7, 14, 14, 21, 14, 28, 14;
%e 8, 16, 16, 24, 16, 32, 16, 32;
%e ...
%e T(6,3) = 12 = 6*d(3) = 6*2, where A000005 = d(k) = (1, 2, 3, 2, 2, 4, 2, 4, 3, ...).
%o (PARI) tabl(nn) = for (n=1, nn, for (k=1, n, print1(n*numdiv(k), ", "))); \\ _Michel Marcus_, Mar 19 2016
%Y Cf. A000005, A127648, A130209, A143274.
%K nonn,tabl
%O 1,2
%A _Gary W. Adamson_, Aug 03 2008
%E a(48) = 20 inserted by _Georg Fischer_, Jun 05 2023
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