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%I #15 Jul 07 2017 03:47:36
%S 1,4,5,11,19,15,25,49,55,35,50,105,136,125,70,91,200,280,300,245,126,
%T 154,350,515,600,575,434,210,246,574,875,1075,1125,1001,714,330,375,
%U 894,1400,1785,1975,1925,1624,1110,495,550,1335,2136,2800,3220,3325,3080,2496,1650,715,781,1925,3135,4200,4970,5341,5250,4680,3675,2365,1001,1079,2695,4455,6075,7350,8134,8330,7890,6825,5225,3289,1365,1456,3679,6160,8525,10500,11886,12544,12390,11400,9625,7216,4459,1820,1925,4914,8320,11660
%N Second accumulation array, T, of the natural number array A000027, by antidiagonals.
%C See A144112 (and A185506) for the definition of accumulation array (aa).
%C Sequence is aa(aa(A000027)).
%H G. C. Greubel, <a href="/A185507/b185507.txt">Table of n, a(n) for the first 50 rows, flattened</a>
%F T(n,k) = k*n*(k+1)*(n+1)*(3*n^2 + (4*k+11)*n + 3*k^2 - k + 16)/144.
%e Northwest corner:
%e 1, 4, 11, 25, 50, 91, 154
%e 5, 19, 49, 105, 200, 350, 574
%e 15, 55, 136, 280, 515, 875, 1400
%e 35, 125, 300, 600, 1075, 1785, 2800
%e 70, 245, 575, 1125, 1975, 3220, 4970
%t g[n_,k_]:=k*n(k+1)(n+1)(3n^2+(4k+11)n+3k^2-k+16)/144;
%t TableForm[Table[g[n,k],{n,1,10},{k,1,15}]]
%t Table[g[n-k+1,k],{n,14},{k,n,1,-1}]//Flatten
%Y Cf. A006522 (row 1), A000332 (column 1).
%Y Cf. A000027, A185506, A185508, A185509.
%K nonn,tabl
%O 1,2
%A _Clark Kimberling_, Jan 29 2011
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