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A117941 Inverse of number triangle A117939. 3

%I #15 Nov 12 2021 12:24:05

%S 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,

%T -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,

%U 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

%N Inverse of number triangle A117939.

%C Row sums are A117942.

%C T(n, k) mod 2 = A117944(n,k).

%H G. C. Greubel, <a href="/A117941/b117941.txt">Rows n = 0..50 of the triangle, flattened</a>

%e Triangle begins

%e 1;

%e -2, 1;

%e -5, 2, 1;

%e -2, 0, 0, 1;

%e 4, -2, 0, -2, 1;

%e 10, -4, -2, -5, 2, 1;

%e -5, 0, 0, 2, 0, 0, 1;

%e 10, -5, 0, -4, 2, 0, -2, 1;

%e 25, -10, -5, -10, 4, 2, -5, 2, 1;

%t 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];

%t m:= m= With[{q = 60}, Table[M[n, k], {n,0,q}, {k,0,q}]];

%t T[n_, k_]:= Inverse[m][[n+1, k+1]];

%t Table[T[n, k], {n,0,15}, {k,0,n}]//Flatten (* _G. C. Greubel_, Oct 29 2021 *)

%Y Cf. A117939, A117942, A117944.

%K sign,tabl

%O 0,2

%A _Paul Barry_, Apr 05 2006

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Last modified April 24 05:36 EDT 2024. Contains 371918 sequences. (Running on oeis4.)