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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
OFFSET
1,2
COMMENTS
See A144112 (and A185506) for the definition of accumulation array (aa).
Sequence is aa(aa(aa(A000027))).
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. A000389 (column 1), A257199 (row 1).
Sequence in context: A186696 A034454 A246715 * A358091 A257338 A059013
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Jan 29 2011
STATUS
approved