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A117941 Inverse of number triangle A117939. 3
1, -2, 1, -5, 2, 1, -2, 0, 0, 1, 4, -2, 0, -2, 1, 10, -4, -2, -5, 2, 1, -5, 0, 0, 2, 0, 0, 1, 10, -5, 0, -4, 2, 0, -2, 1, 25, -10, -5, -10, 4, 2, -5, 2, 1, -2, 0, 0, 0, 0, 0, 0, 0, 0, 1, 4, -2, 0, 0, 0, 0, 0, 0, 0, -2, 1, 10, -4, -2, 0, 0, 0, 0, 0, 0, -5, 2, 1, 4, 0, 0, -2, 0, 0, 0, 0, 0, -2, 0, 0, 1, -8, 4, 0, 4, -2, 0, 0, 0, 0, 4, -2, 0, -2, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
Row sums are A117942.
T(n, k) mod 2 = A117944(n,k).
LINKS
EXAMPLE
Triangle begins
1;
-2, 1;
-5, 2, 1;
-2, 0, 0, 1;
4, -2, 0, -2, 1;
10, -4, -2, -5, 2, 1;
-5, 0, 0, 2, 0, 0, 1;
10, -5, 0, -4, 2, 0, -2, 1;
25, -10, -5, -10, 4, 2, -5, 2, 1;
MATHEMATICA
M[n_, k_]:= M[n, k]= If[k>n, 0, Sum[JacobiSymbol[Binomial[n, j], 3]*JacobiSymbol[Binomial[n-j, k], 3], {j, 0, n}], 0];
m:= m= With[{q = 60}, Table[M[n, k], {n, 0, q}, {k, 0, q}]];
T[n_, k_]:= Inverse[m][[n+1, k+1]];
Table[T[n, k], {n, 0, 15}, {k, 0, n}]//Flatten (* G. C. Greubel, Oct 29 2021 *)
CROSSREFS
Sequence in context: A006556 A108790 A355914 * A134566 A128694 A088421
KEYWORD
sign,tabl
AUTHOR
Paul Barry, Apr 05 2006
STATUS
approved

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Last modified June 20 11:12 EDT 2024. Contains 373527 sequences. (Running on oeis4.)