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A118013 Triangle read by rows: T(n,k) = floor(n^2/k), 1<=k<=n.

%I A118013 #13 Jul 13 2013 12:03:23
%S A118013 1,4,2,9,4,3,16,8,5,4,25,12,8,6,5,36,18,12,9,7,6,49,24,16,12,9,8,7,64,
%T A118013 32,21,16,12,10,9,8,81,40,27,20,16,13,11,10,9,100,50,33,25,20,16,14,
%U A118013 12,11,10,121,60,40,30,24,20,17,15,13,12,11,144,72,48,36,28,24,20,18,16,14
%N A118013 Triangle read by rows: T(n,k) = floor(n^2/k), 1<=k<=n.
%C A118013 T(n,1) = A000290(n); T(n,n) = n;
%C A118013 T(n,2) = A007590(n) for n>1;
%C A118013 T(n,3) = A000212(n) for n>2;
%C A118013 T(n,4) = A002620(n) for n>3;
%C A118013 T(n,5) = A118015(n) for n>4;
%C A118013 T(n,6) = A056827(n) for n>5;
%C A118013 central terms give A008574: T(2*k-1,k) = 4*(k-1)+0^(k-1);
%C A118013 row sums give A118014.
%H A118013 Reinhard Zumkeller, <a href="/A118013/b118013.txt">Rows n=1..100 of triangle, flattened</a>
%e A118013 Triangle begins:
%e A118013 1,
%e A118013 4, 2,
%e A118013 9, 4, 3,
%e A118013 16, 8, 5, 4,
%o A118013 (PARI) T(n,k)=n^2\k \\ _Charles R Greathouse IV_, Jan 15 2012
%o A118013 (Haskell)
%o A118013 a118013 n k = a118013_tabl !! (n-1) !! (k-1)
%o A118013 a118013_row n = map (div (n^2)) [1..n]
%o A118013 a118013_tabl = map a118013_row [1..]
%o A118013 -- _Reinhard Zumkeller_, Jan 22 2012
%Y A118013 Cf. A010766.
%K A118013 nonn,easy,tabl
%O A118013 1,2
%A A118013 _Reinhard Zumkeller_, Apr 10 2006