cp's OEIS Frontend

A108035 Triangle read by rows: n-th row consists of n copies of the n-th nonzero Fibonacci number.

%I A108035 #19 Nov 09 2024 01:14:03
%S A108035 1,2,2,3,3,3,5,5,5,5,8,8,8,8,8,13,13,13,13,13,13,21,21,21,21,21,21,21,
%T A108035 34,34,34,34,34,34,34,34,55,55,55,55,55,55,55,55,55,89,89,89,89,89,89,
%U A108035 89,89,89,89,144,144,144,144,144,144,144,144,144,144,144,233,233,233,233,233,233,233,233,233,233,233,233
%N A108035 Triangle read by rows: n-th row consists of n copies of the n-th nonzero Fibonacci number.
%H A108035 Reinhard Zumkeller, <a href="/A108035/b108035.txt">Rows n = 1..120 of triangle, flattened</a>
%F A108035 G.f.: (1+x+y)/((1-x-x^2)*(1-y-y^2)). [U coordinates]
%e A108035 1; 2,2; 3,3,3; 5,5,5,5; 8,8,8,8,8; ...
%t A108035 Flatten[Table[Table[Fibonacci[n],{n-1}],{n,13}]] (* _Harvey P. Dale_, Jul 18 2015 *)
%o A108035 (Haskell)
%o A108035 a108035 n k = a108035_tabl !! (n-1) !! (n-1)
%o A108035 a108035_row n = a108035_tabl !! (n-1)
%o A108035 a108035_tabl = zipWith replicate [1..] $ drop 2 a000045_list
%o A108035 -- _Reinhard Zumkeller_, Oct 07 2012
%o A108035 (Python)
%o A108035 from math import isqrt
%o A108035 from sympy import fibonacci
%o A108035 def A108035(n): return int(fibonacci(1+(m:=isqrt(k:=n<<1))+(k>m*(m+1)))) # _Chai Wah Wu_, Nov 07 2024
%Y A108035 Cf. A000045, A039913, A108036, A108037.
%Y A108035 Cf. A023607 (row sums).
%K A108035 nonn,tabl
%O A108035 1,2
%A A108035 _N. J. A. Sloane_, Jun 01 2005
%E A108035 Definition clarified by _N. J. A. Sloane_, Nov 09 2024