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A119445 Leading diagonal of triangle A119444.

%I A119445 #13 Apr 07 2023 08:57:35
%S A119445 1,1,1,1,1,3,7,13,27,63,109,207,331,553,931,1531,2527,4093,6673,10831,
%T A119445 17563,28561,46227,74883,121219,196239,317607,514047,831823,1346041,
%U A119445 2178079,3524323,5702619,9227161,14930019,24157471,39087823,63245551
%N A119445 Leading diagonal of triangle A119444.
%H A119445 G. C. Greubel, <a href="/A119445/b119445.txt">Table of n, a(n) for n = 1..1000</a>
%F A119445 a(n) = A119444(n, n).
%t A119445 t[1, n_]:= Fibonacci[n+1];  (* t = A119444 *)
%t A119445 t[m_, n_]/; 1<m<=n:= t[m, n]= (n-m+1)*Floor[(t[m-1,n] -1)/(n-m+1)];
%t A119445 t[_, _]= 0;
%t A119445 A119445[n_]:= A119445[n]= t[n,n];
%t A119445 Table[A119445[n], {n,60}] (* _G. C. Greubel_, Apr 07 2023 *)
%o A119445 (Magma)
%o A119445 function t(n,k) // t = A119444
%o A119445   if k eq 1 then return Fibonacci(n+1);
%o A119445   else return (n-k+1)*Floor((t(n,k-1) -1)/(n-k+1));
%o A119445   end if;
%o A119445 end function;
%o A119445 [t(n,n): n in [1..60]]; // _G. C. Greubel_, Apr 07 2023
%o A119445 (SageMath)
%o A119445 def t(n, k): # t = A119444
%o A119445     if (k==1): return fibonacci(n+1)
%o A119445     else: return (n-k+1)*((t(n, k-1) -1)//(n-k+1))
%o A119445 def A119445(n): return t(n,n)
%o A119445 [A119445(n) for n in range(1,61)] # _G. C. Greubel_, Apr 07 2023
%Y A119445 Cf. A119444 for triangle corresponding to this sequence.
%Y A119445 Cf. A100461 for powers of 2, A119446 for primes.
%K A119445 nonn
%O A119445 1,6
%A A119445 _Joshua Zucker_, May 20 2006