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A237684 a(n) = floor(n*prime(n) / Sum_{i<=n} prime(i). 1
1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

COMMENTS

a(n) = 1 for n = 8 and 1 <= n <=6.

a(n) = 2 for n = 7 and 9 <= n < 10^11 (verified terms).

Conjectures:

(1): a(n) = 1 or 2 for all n.

(2): sequence of numbers n sorted by decreasing values of function f(n) = n*Prime(n) / Sum_i<=n (Prime(i): 48, 35, 31, 25, 17, 49, 33, 69, 32, 26, 43, 38, 12, 63, 102, 67, 68, 37, … The last term of this sequence is 1.

(3): maximal value of function f(n) is for n = 48: f(48) = 10704/4661 = 2.29650289637416...

(4): minimal value of function f(n) is for n = 1: f(1) = 1.

LINKS

Jaroslav Krizek, Table of n, a(n) for n = 1..87

FORMULA

a(n) = floor(A033286(n) / A007504(n)).

EXAMPLE

For n=8: a(8) = floor(8*Prime(8) / Sum_i<=8 (Prime(i)) = 8*19 / 77 = 1.

CROSSREFS

Sequence in context: A297784 A043568 A043543 * A130634 A274828 A257474

Adjacent sequences:  A237681 A237682 A237683 * A237685 A237686 A237687

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, Feb 21 2014

STATUS

approved

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Last modified October 31 19:00 EDT 2020. Contains 338111 sequences. (Running on oeis4.)