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Ady's RH problem (Posted on 2014-03-11) Difficulty: 4 of 5
Let

Sequence1= (all existing 4-digit numbers, no leading zeros);
Sequence2= (each member of seq1 replaced by 1 iff fulfilling both conditions : cond1 and cond2; replaced by 0 otherwise.)

Cond1: k (the number of letters in the English set of words representing N) is even.
For example the number 3024 (three thousand twenty four) does not qualify (23 letters) .

Cond2: the number N is evenly divisible by 3, e.g. the number 3024 qualifies.

Ergo: 3024 of Sequence1 will be replaced by 0 in Sequence2.

Denote by N1 the number of ones in the seq2 and by N0 the number of zeroes in that sequence.

Don't be intimidated by the D4 label,- reread the text carefully and try to answer all of the following questions:

a. What does the RH stand for?
b. Is it true that abs(N1- N0) is an even number?
c. What is the meaning of KISS?
d. Why D4?

See The Solution Submitted by Ady TZIDON    
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Solution re(2): Half-serious answer | Comment 4 of 6 |
(In reply to re: Half-serious answer by Ady TZIDON)

"Please answer truthfully, did my "Freudian slip" re "always" guide you?"

Haha, no, I don't think so.  I knew that B was necessarily yes almost immediately upon reading the problem.  I had no idea what the rest meant.  I thought maybe once I derived Sequence 2, there would be some pattern that might give a hint to the meanings of RH and/or KISS or something, but after doing it, I didn't see anything.  

Then it occurred to me that if the sequence didn't contain a clue to the meanings of those acronyms, there really wasn't any reason to have done the work to derive the sequence at all, since you don't need it for part (b) either.  I couldn't think of any other meaning for KISS than the well-known acronym, so I figured I'd keep it simple and just guess at the other parts, but I didn't expect that they'd be right. :)



  Posted by tomarken on 2014-03-11 17:08:33
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