cp's OEIS Frontend

A119789 T(n, k) = floor(log_{goldenratio}(Fibonacci(n)*Fibonacci(k))), with T(n, k) = 0 for n < 3, T(n, 0) = n-2 for n > 2, triangle read by rows.

%I A119789 #13 Dec 19 2022 03:26:17
%S A119789 0,0,0,0,0,0,1,1,1,2,2,2,2,3,4,3,3,3,4,5,6,4,4,4,5,6,7,8,5,5,5,6,7,8,
%T A119789 9,10,6,6,6,7,8,9,10,11,12,7,7,7,8,9,10,11,12,13,14,8,8,8,9,10,11,12,
%U A119789 13,14,15,16
%N A119789 T(n, k) = floor(log_{goldenratio}(Fibonacci(n)*Fibonacci(k))), with T(n, k) = 0 for n < 3, T(n, 0) = n-2 for n > 2, triangle read by rows.
%H A119789 G. C. Greubel, <a href="/A119789/b119789.txt">Rows n = 0..50 of the triangle, flattened</a>
%F A119789 T(n, k) = floor(log_{goldenratio}(Fibonacci(n)*Fibonacci(k))), with T(n, k) = 0 for n < 3, T(n, 0) = n-2 for n > 2.
%F A119789 From _G. C. Greubel_, Dec 17 2022: (Start)
%F A119789 T(n, k) = n+k-4, with T(n, k) = 0 for n < 3, T(n, 0) = n-2 for n >= 3.
%F A119789 T(n, n) = 2*T(n, 0).
%F A119789 T(2*n, n) = 0*[n<2] + A016789(n-2)*[n>1].
%F A119789 T(2*n, n+1) = 3*A001477(n-1), for n > 0.
%F A119789 T(2*n, n-1) = A033627(n) - [n=1].
%F A119789 T(3*n, n) = n*[n<2] + 4*A000027(n-2)*[n>1].
%F A119789 Sum_{k=0..n} T(n, k) = 0*[n<2] + A140090(n-2)*[n>1].
%F A119789 Sum_{k=0..n} (-1)^k * T(n, k) = 0*[n<2] + (-1)^n*A064455(n-2)*[n>1]. (End)
%e A119789 Triangle begins as:
%e A119789   0;
%e A119789   0, 0;
%e A119789   0, 0, 0;
%e A119789   1, 1, 1, 2;
%e A119789   2, 2, 2, 3, 4;
%e A119789   3, 3, 3, 4, 5, 6;
%e A119789   4, 4, 4, 5, 6, 7, 8;
%e A119789   5, 5, 5, 6, 7, 8, 9, 10;
%t A119789 f[n_, k_]= If[n<3, 0, If[k==0, n-2, Floor[Log[GoldenRatio, Fibonacci[n]*Fibonacci[k]]]]];
%t A119789 Table[f[n, k], {n,0,12}, {k,0,n}]//Flatten
%t A119789 (* Second program *)
%t A119789 T[n_, k_]:= T[n, k]= If[n<3, 0, If[k<2, n-2, n+k-4]];
%t A119789 Table[T[n, k], {n,0,12}, {k,0,n}]//Flatten (* _G. C. Greubel_, Dec 17 2022 *)
%o A119789 (Magma)
%o A119789 A119789:= func< n,k | n le 2 select 0 else k le 1 select n-2 else n+k-4 >;
%o A119789 [A119789(n,k): k in [0..n], n in [0..12]]; // _G. C. Greubel_, Dec 17 2022
%o A119789 (SageMath)
%o A119789 def A119789(n,k):
%o A119789     if (n<3): return 0
%o A119789     elif (k<2): return n-2
%o A119789     else: return n+k-4
%o A119789 flatten([[A119789(n,k) for k in range(n+1)] for n in range(13)]) # _G. C. Greubel_, Dec 17 2022
%Y A119789 Cf. A000045, A001477, A016789, A033627, A035517, A064455, A140090.
%K A119789 nonn,tabl
%O A119789 0,10
%A A119789 _Roger L. Bagula_, Jul 30 2006
%E A119789 Edited by _G. C. Greubel_, Dec 17 2022