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A185509
Fourth accumulation array, T, of the natural number array A000027, by antidiagonals.
5
1, 6, 7, 22, 41, 28, 63, 146, 161, 84, 154, 406, 561, 476, 210, 336, 966, 1526, 1631, 1176, 462, 672, 2058, 3556, 4361, 3976, 2562, 924, 1254, 4032, 7434, 9996, 10486, 8568, 5082, 1716, 2211, 7392, 14322, 20580, 23716, 22344, 16842, 9372, 3003, 3718, 12837, 25872, 39102, 48216, 49980, 43512, 30822, 16302, 5005, 6006, 21307, 44352, 69762, 90552, 100548, 96432, 79002, 53262, 27027, 8008, 9373, 34034, 72787, 118272, 159852
OFFSET
1,2
COMMENTS
See A144112 (and A185506) for the definition of rectangular sum array (aa).
Sequence is aa(aa(aa(aa(A000027)))).
FORMULA
T(n,k) = F*(5*n^2 + (6*k + 39)*n + 5*k^2 + 9*k + 86), where
F = k*(k+1)*(k+2)*(k+3)*n*(n+1)*(n+2)*(n+3)/86400.
EXAMPLE
Northwest corner:
1.....6....22....63...154
7....41...146...406...966
28..161...561..1526..3556
84..476..1631..4361..9996
MATHEMATICA
u[n_, k_]:=k(k+1)(k+2)(k+3)n(n+1)(n+2)(n+3)(5n^2+(6k+39)n+5k^2+9k+86)/86400
TableForm[Table[u[n, k], {n, 1, 10}, {k, 1, 15}]]
Table[u[n-k+1, k], {n, 14}, {k, n, 1, -1}]//Flatten
CROSSREFS
Cf. A000579 (column 1), A257200 (row 1).
Sequence in context: A048062 A295729 A081284 * A099572 A288705 A287097
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Jan 29 2011
STATUS
approved