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%I #14 Jun 19 2014 04:50:53
%S 1,1,2,1,2,2,2,1,3,1,2,2,3,1,3,1,3,2,2,1,4,1,2,2,3,2,3,1,3,2,3,1,4,1,
%T 2,3,3,1,3,1,4,2,2,1,4,2,2,2,3,1,4,1,3,2,2,2,4,1,2,2,4,1,3,1,3,3,2,1,
%U 4,1,3,2,3,1,3,2,3,2,2,1,5,1,2,2,3,2,4,1,3,2,3,1,5,1,2,3,3,1,4,1,4,2,2,1,5
%N Table read by rows: T(n,k) is the number of divisors of k that are <= n.
%C Suggested by a question from _Eric Desbiaux_.
%C The row lengths are the lengths before the pattern for n repeats.
%C Antidiagonal sums A070824. [From _Eric Desbiaux_, Dec 10 2009]
%F T(n,k) = sum_{i|k, i<=n} 1.
%e The first few rows start:
%e 1, [A000012]
%e 1, 2, [A000034]
%e 1, 2, 2, 2, 1, 3, [A083039]
%e 1, 2, 2, 3, 1, 3, 1, 3, 2, 2, 1, 4, [A083040]
%o (PARI) lista(nrows) = {for (n=1, nrows, for (k=1, lcm(vector(n, i, i)), print1(sumdiv(k, d, d <=n), ", ");); print(););} \\ _Michel Marcus_, Jun 19 2014
%Y Row lengths A003418, row sums A025529, frequencies in rows A096180.
%Y Cf. A243987
%K easy,nonn,tabf
%O 1,3
%A _Franklin T. Adams-Watters_, Mar 24 2008
%E Definition corrected by _Franklin T. Adams-Watters_, Jun 19 2014
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