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 A185508 Third accumulation array, T, of the natural number array A000027, by antidiagonals. 6
 1, 5, 6, 16, 29, 21, 41, 89, 99, 56, 91, 219, 295, 259, 126, 182, 469, 705, 755, 574, 252, 336, 910, 1470, 1765, 1645, 1134, 462, 582, 1638, 2786, 3605, 3780, 3206, 2058, 792, 957, 2778, 4914, 6706, 7595, 7266, 5754, 3498, 1287, 1507, 4488, 8190, 11634, 13916, 14406, 12894, 9690, 5643, 2002, 2288, 6963, 13035, 19110, 23814, 26068, 25284, 21510, 15510, 8723, 3003, 3367, 10439, 19965, 30030, 38640, 44100 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See A144112 (and A185506) for the definition of accumulation array (aa). Sequence is aa(aa(aa(A000027))). LINKS G. C. Greubel, Table of n, a(n) for the first 50 rows, flattened FORMULA T(n,k) = F*(4n^2 + (5k+23)n + 4k^2 + 3k+41), where F = k(k+1)(k+2)n(n+1)(n+2)/2880. EXAMPLE Northwest corner:    1    5   16   41   91  182    6   29   89  219  469  910   21   99  295  705 1470 2786   56  259  755 1765 3605 6706 MATHEMATICA h[n_, k_]:=k(k+1)(k+2)n(n+1)(n+2)*(4n^2+(5k+23)n+4k^2+3k+41)/2880; TableForm[Table[h[n, k], {n, 1, 10}, {k, 1, 15}]] Table[h[n-k+1, k], {n, 14}, {k, n, 1, -1}]//Flatten PROG (PARI) {h(n, k) = k*(k+1)*(k+2)*n*(n+1)*(n+2)*(4*n^2+(5*k+23)*n +4*k^2 +3*k + 41)/2880}; for(n=1, 10, for(k=1, n, print1(h(k, n-k+1), ", "))) \\ G. C. Greubel, Nov 23 2017 CROSSREFS Cf. A000027, A185506, A185507, A185509. Cf. A000389 (column 1), A257199 (row 1). Sequence in context: A186696 A034454 A246715 * A257338 A059013 A327102 Adjacent sequences:  A185505 A185506 A185507 * A185509 A185510 A185511 KEYWORD nonn,tabl AUTHOR Clark Kimberling, Jan 29 2011 STATUS approved

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Last modified April 21 03:28 EDT 2021. Contains 343145 sequences. (Running on oeis4.)