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A300836
a(n) is the total number of terms (1-digits) in Zeckendorf representation of all proper divisors of n.
8
0, 1, 1, 2, 1, 3, 1, 4, 2, 3, 1, 7, 1, 4, 3, 5, 1, 7, 1, 7, 4, 4, 1, 11, 2, 3, 4, 8, 1, 10, 1, 7, 4, 5, 4, 14, 1, 5, 3, 11, 1, 10, 1, 8, 7, 4, 1, 15, 3, 8, 5, 7, 1, 12, 4, 12, 5, 4, 1, 21, 1, 5, 7, 10, 3, 13, 1, 8, 4, 11, 1, 19, 1, 4, 8, 10, 5, 10, 1, 16, 7, 5, 1, 20, 5, 5, 4, 12, 1, 20, 4, 10, 5, 4, 5, 21, 1, 9, 10, 16, 1, 13, 1, 11, 10
OFFSET
1,4
LINKS
FORMULA
a(n) = Sum_{d|n, d<n} A007895(d).
a(n) = A300837(n) - A007895(n).
a(n) = A001222(A300834(n)).
For all n >=1, a(n) >= A293435(n).
EXAMPLE
For n=12, its proper divisors are 1, 2, 3, 4 and 6. Zeckendorf-representations (A014417) of these numbers are 1, 10, 100, 101 and 1001. Total number of 1's present is 7, thus a(12) = 7.
PROG
(PARI)
A072649(n) = { my(m); if(n<1, 0, m=0; until(fibonacci(m)>n, m++); m-2); }; \\ From A072649
A007895(n) = { my(s=0); while(n>0, s++; n -= fibonacci(1+A072649(n))); (s); }
A300836(n) = sumdiv(n, d, (d<n)*A007895(d));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 18 2018
STATUS
approved