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A276646
a(n) = floor(Sum_{k=1..n} 0.k).
1
0, 0, 0, 1, 1, 2, 2, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12, 13, 13, 13, 14, 14, 15, 15, 16, 16, 17, 17, 18, 18, 19, 20, 20, 21, 21, 22, 22, 23, 24, 24, 25, 26, 26, 27, 28, 28, 29, 30, 31
OFFSET
1,6
COMMENTS
Here 0.k means the decimal fraction obtained by writing k after the decimal point, e.g. 0.12 = 12/100 = 3/25.
The first few values of Sum_{k=1..n} 0.k are: 1/10, 3/10, 3/5, 1, 3/2, 21/10, 14/5, 18/5, 9/2, 23/5, ...
Conjecture: function ((Sum_{k=1..n} 0.k) / n) is bounded above by values 0.55.
LINKS
FORMULA
a(n) = floor(A275625(n)/A275626(n)).
EXAMPLE
For n=12; a(12) = floor(Sum_{k=1..12} 0.k) = floor(0.1 + 0.2 + 0.3 + 0.4 + 0.5 + 0.6 + 0.7 + 0.8 + 0.9 + 0.10 + 0.11 + 0.12 = 4.83) = floor(483/100) = 4.
PROG
(Magma) [Floor(&+[k / (10^(#Intseq(k))): k in [1..n]]): n in [1..1000]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Sep 09 2016
STATUS
approved