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A008969
Triangle of differences of reciprocals of unity.
16
1, 1, 3, 1, 11, 7, 1, 50, 85, 15, 1, 274, 1660, 575, 31, 1, 1764, 48076, 46760, 3661, 63, 1, 13068, 1942416, 6998824, 1217776, 22631, 127, 1, 109584, 104587344, 1744835904, 929081776, 30480800, 137845, 255, 1, 1026576, 7245893376, 673781602752, 1413470290176, 117550462624, 747497920, 833375, 511
OFFSET
1,3
REFERENCES
F. N. David, M. G. Kendall and D. E. Barton, Symmetric Function and Allied Tables, Cambridge, 1966, p. 228.
LINKS
EXAMPLE
Triangle T(n,k) begins:
1;
1, 3;
1, 11, 7;
1, 50, 85, 15;
1, 274, 1660, 575, 31;
1, 1764, 48076, 46760, 3661, 63;
1, 13068, 1942416, 6998824, 1217776, 22631, 127;
1, 109584, 104587344, 1744835904, 929081776, 30480800, 137845, 255;
...
MAPLE
T:= (n, k)-> `if`(k<=n, (n-k+2)!^k *
add((-1)^(j+1)*binomial(n-k+2, j)/ j^k, j=1..n-k+2), 0):
seq(seq(T(n, k), k=0..n), n=0..7); # Alois P. Heinz, Sep 05 2008
MATHEMATICA
T[n_, k_] := If[k <= n, (n-k+2)!^k*Sum[(-1)^(j+1)*Binomial[n-k+2, j]/j^k, {j, 1, n-k+2}], 0]; Table[Table[T[n, k], {k, 0, n}], {n, 0, 7}] // Flatten (* Jean-François Alcover, Mar 10 2014, after Alois P. Heinz *)
CROSSREFS
Columns include A000254, A000424, A001236, A001237, A001238. Right-hand columns include A000225, A001240, A001241, A001242.
Sequence in context: A111965 A110440 A135574 * A199577 A228534 A119908
KEYWORD
nonn,tabl
AUTHOR
STATUS
approved