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A328208
Zeckendorf-Niven numbers: numbers divisible by the number of terms in their Zeckendorf representation (A007895).
39
1, 2, 3, 4, 5, 6, 8, 10, 12, 13, 14, 16, 18, 21, 22, 24, 26, 27, 30, 34, 36, 42, 45, 48, 55, 56, 58, 60, 66, 68, 69, 72, 76, 78, 80, 81, 84, 89, 90, 92, 93, 94, 96, 99, 102, 105, 108, 110, 111, 116, 120, 126, 132, 135, 140, 144, 146, 150, 152, 153, 156, 159, 162
OFFSET
1,2
REFERENCES
Andrew Ray, On the natural density of the k-Zeckendorf Niven numbers, Ph.D. dissertation, Central Missouri State University, 2005.
LINKS
Helen G. Grundman, Consecutive Zeckendorf-Niven and lazy-Fibonacci-Niven numbers, Fibonacci Quarterly, Vol. 45, No. 3 (2007), pp. 272-276.
Andrew Ray and Curtis Cooper, On the natural density of the k-Zeckendorf Niven numbers, J. Inst. Math. Comput. Sci. Math., Vol. 19 (2006), pp. 83-98.
EXAMPLE
12 is in the sequence since A007895(12) = 3 and 3 is a divisor of 12.
MAPLE
fib:= combinat:-fibonacci:
phi:= 1/2 + sqrt(5)/2:
fibapp:= n -> phi^n/sqrt(5):
invfib := proc(x::posint)
local q, n;
q:= evalf((ln(x+1/2) + ln(5)/2)/ln(phi));
n:= floor(q);
if fib(n) <= x then
while fib(n+1) <= x do
n := n+1
end do
else
while fib(n) > x do
n := n-1
end do
end if;
n
end proc:
zeck:= proc(x) local n;
if x = 0 then 0
else
n:= invfib(x);
F[n] + zeck(x-fib(n));
fi
end proc:
filter:= n -> n mod nops(zeck(n)) = 0:
select(filter, [$1..200]); # Robert Israel, Oct 25 2019
MATHEMATICA
z[n_] := Length[DeleteCases[NestWhileList[# - Fibonacci[Floor[Log[Sqrt[5]*# + 3/2]/Log[GoldenRatio]]] &, n, # > 1 &], 0]]; aQ[n_] := Divisible[n, z[n]]; Select[Range[1000], aQ] (* after Alonso del Arte at A007895 *)
CROSSREFS
Sequence in context: A005423 A067319 A086049 * A173643 A377209 A377210
KEYWORD
nonn
AUTHOR
Amiram Eldar, Oct 07 2019
STATUS
approved