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 A185730 Array by antidiagonals: T(n,k)=k(k+1)n(n+1)(kn-n+2k+7)/36. 1
 1, 4, 3, 10, 13, 6, 20, 34, 28, 10, 35, 70, 76, 50, 15, 56, 125, 160, 140, 80, 21, 84, 203, 290, 300, 230, 119, 28, 120, 308, 476, 550, 500, 350, 168, 36, 165, 444, 728, 910, 925, 770, 504, 228, 45, 220, 615, 1056, 1400, 1540, 1435, 1120, 696, 300, 55, 286, 825, 1470, 2040, 2380, 2401, 2100, 1560, 930, 385, 66, 364, 1078, 1980, 2850, 3480, 3724, 3528, 2940 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS This array is a member of a chain of arrays; it is the accumulation array of the array obtain by writing A125764 rectangularly - 1...3....6....10... 2...7....15...26... 3...12...27...48... and it is the weight array of A185731.  (Weight and accumulation arrays are defined at A144112.) LINKS FORMULA T(n,k)=k(k+1)n(n+1)(kn-n+2k+7)/36. EXAMPLE Northwest corner: 1....4....10....20....35 3....13...34....70....125 6....28...76....160...290 10...50...140...300...550 15...80...230...500...925 MATHEMATICA f[n_, k_]:=k(1+k)n(1+n)(7+2k-n+k*n)/36; TableForm[Table[f[n, k], {n, 1, 10}, {k, 1, 15}]] Table[f[n-k+1, k], {n, 14}, {k, n, 1, -1}]//Flatten CROSSREFS Cf. A144112, A125764, A185731. Sequence in context: A081617 A103252 A065763 * A205965 A222510 A100492 Adjacent sequences:  A185727 A185728 A185729 * A185731 A185732 A185733 KEYWORD nonn,tabl AUTHOR Clark Kimberling, Feb 01 2011 STATUS approved

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