About Convergence of a particular sequence

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SUMMARY

The discussion focuses on proving the convergence of the sequence defined by {b_n}, where all terms are nonnegative and satisfy the condition b_{i+j} <= b_i + b_j for i, j >= 1. Participants established that b_n/n <= b_1 for all n, indicating that the sequence is bounded. The key challenge is demonstrating that the sequence (b_n)/n is monotonic from some index N onward, which is essential for proving its convergence. The use of induction and integral tests were suggested as methods to further explore this proof.

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Homework Statement

let's define {b_n} as an infinite sequence such that
all terms are nonnegative, and
for any i, j >= 1,

b_{i+j} <= b_i + b_j

it's easy to show that b_n/n <= (b_1) for all n, but
how would you show that
{(b_n)/n} is a convergent sequence?

Homework Equations


The Attempt at a Solution


Homework Statement


Homework Equations


The Attempt at a Solution



Using induction, I got upto 0 < = b_n / n < = b_1
but that was pretty much it.
I have to show that it's monotone from some N on or something like that, i think..
but I'm just stuck about how to show that.
 
Last edited:
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If you've shown b_n<b_1/n then b_n/n<b_1/n^2. Can you show b_1/n^2 is a convergent sequence? An integral test should work.
 
my bad, problem fixed. i meant b_n < = b_1
 

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