All about
flooble

fun stuff

Get a free chatterbox

Free JavaScript

Avatars
perplexus
dot
info
Home
>
Numbers
>
Sequences
At least 3 zeroes (
Posted on 20181003
)
How many binary strings of length n, having three or more zeroes, exist?
No Solution Yet
Submitted by
Ady TZIDON
No Rating
Comments: (
Back to comment list
 You must be logged in to post comments.
)
solution
 Comment 2 of 5 
Altogether there are 2^n binary strings of length n. There is 1 that has no zeros, n that have one zero and C(n,2)=n*(n1)/2 that have two zeros.
The answer is
2^n  1  n  n*(n1)/2
=
2^n  (n^2+n)/2  1
Posted by
Charlie
on 20181003 11:58:11
Please log in:
Login:
Password:
Remember me:
Sign up!

Forgot password
Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ

About This Site
Site Statistics
New Comments (4)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On
Chatterbox:
blackjack
flooble's webmaster puzzle
Copyright © 2002  2018 by
Animus Pactum Consulting
. All rights reserved.
Privacy Information