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A108035
Triangle read by rows: n-th row consists of n copies of the n-th nonzero Fibonacci number.
5
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, 34, 34, 34, 34, 34, 34, 34, 34, 55, 55, 55, 55, 55, 55, 55, 55, 55, 89, 89, 89, 89, 89, 89, 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
OFFSET
1,2
LINKS
FORMULA
G.f.: (1+x+y)/((1-x-x^2)*(1-y-y^2)). [U coordinates]
EXAMPLE
1; 2,2; 3,3,3; 5,5,5,5; 8,8,8,8,8; ...
MATHEMATICA
Flatten[Table[Table[Fibonacci[n], {n-1}], {n, 13}]] (* Harvey P. Dale, Jul 18 2015 *)
PROG
(Haskell)
a108035 n k = a108035_tabl !! (n-1) !! (n-1)
a108035_row n = a108035_tabl !! (n-1)
a108035_tabl = zipWith replicate [1..] $ drop 2 a000045_list
-- Reinhard Zumkeller, Oct 07 2012
(Python)
from math import isqrt
from sympy import fibonacci
def A108035(n): return int(fibonacci(1+(m:=isqrt(k:=n<<1))+(k>m*(m+1)))) # Chai Wah Wu, Nov 07 2024
CROSSREFS
Cf. A023607 (row sums).
Sequence in context: A295629 A076272 A180101 * A202503 A049747 A260684
KEYWORD
nonn,tabl
AUTHOR
N. J. A. Sloane, Jun 01 2005
EXTENSIONS
Definition clarified by N. J. A. Sloane, Nov 09 2024
STATUS
approved