All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Numbers
Words count (Posted on 2014-03-25) Difficulty: 4 of 5
(D3)How many subsets of (a,b,c, x,y,z) contain no letters neighboring each other in the English ABC (26 letters)?

(D4)How many "words" (i.e, ordered subsets from (a,b,c, x,y,z)) contain no neighboring letters that neighbor each other in the English ABC (26 letters)?

No Solution Yet Submitted by Ady TZIDON    
No Rating

Comments: ( Back to comment list | You must be logged in to post comments.)
Hints/Tips re: solution to part 1; thoughts on part 2 | Comment 5 of 8 |
(In reply to solution to part 1; thoughts on part 2 by Charlie)

Part 1 is easy.

Part 2 is a D4 question, to which I do not have an "official solution". Since you show a procedure leading to a final answer and it is limited only by size I suggest that you provide 2 "modified"  answers:

1. Part 2 - an exact answer , applied to Hawaian alphabet.

2. Part 2 - an  answer re English ABC, providing intelligent apprroximation (like log a(26).

IMHO - the result of part 2 qualifies to give you credit in OEIS, - the table does not need to reach big-big numbers.

 


  Posted by Ady TZIDON on 2014-03-26 02:25:38
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 (1)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2017 by Animus Pactum Consulting. All rights reserved. Privacy Information