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A219642
Number of steps to reach 0 starting with n and using the iterated process: x -> x - (number of 1's in Zeckendorf expansion of x).
12
0, 1, 2, 3, 3, 4, 4, 5, 6, 6, 7, 7, 7, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 14, 15, 15, 16, 16, 17, 17, 17, 18, 18, 18, 19, 19, 19, 20, 20, 21, 21, 21, 22, 22, 22, 22, 23, 24, 24, 25, 25, 25, 26, 26, 26, 27, 27, 27, 28, 28, 29, 29
OFFSET
0,3
COMMENTS
See A014417 for the Fibonacci number system representation, also known as Zeckendorf expansion.
LINKS
FORMULA
a(0)=0; for n>0, a(n) = 1+a(A219641(n)).
PROG
(Scheme with memoization macro definec from Antti Karttunen's Intseq-library):
(definec (A219642 n) (if (zero? n) n (+ 1 (A219642 (A219641 n)))))
(PARI) A007895(n)=if(n<4, n>0, my(k=2, s, t); while(fibonacci(k++)<=n, ); while(k && n, t=fibonacci(k); if(t<=n, n-=t; s++); k--); s)
a(n)=my(s); while(n, n-=A007895(n); s++); s \\ Charles R Greathouse IV, Sep 02 2015
(Python)
from sympy import fibonacci
def a007895(n):
k=0
x=0
while n>0:
k=0
while fibonacci(k)<=n: k+=1
x+=10**(k - 3)
n-=fibonacci(k - 1)
return str(x).count("1")
def a219641(n): return n - a007895(n)
l=[0]
for n in range(1, 101):
l.append(1 + l[a219641(n)])
print(l) # Indranil Ghosh, Jun 09 2017
CROSSREFS
Cf. A007895, A014417, A219640, A219641, A219643-A219645, A219648. Analogous sequence for binary system: A071542, for factorial number system: A219652.
Sequence in context: A229790 A156261 A071823 * A139338 A244229 A317596
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 24 2012
STATUS
approved