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#3176 Re: Exercises » What do you think? » 2010-04-29 02:21:05

bobbym wrote:

You will see that it requires no more math than you already know.

That should read, "You will see that it requires no more math than you once knew"...although I don't recall ever learning about the Division Algorithm.

Is there a page about the D.A. on MIF? I couldn't find it. Wikipedia covers it, so I'm looking at it over there. But I prefer MIF's explanations as they're more suited to know-nothings like me.

So I haven't got terribly far with your solution just yet...stuck already after just four words into it!

#3177 Re: Exercises » What do you think? » 2010-04-28 14:55:57

Hi Bobby,

Thanks for that solution. I'd thought of applying those divisors to the same dividend, but couldn't progress beyond that thought.

I haven't grasped it fully yet, but will try to do that later.

I came home from work early to try to catch up on some paperwork, but the lure of MIF is eating into my productivity time!

#3178 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-28 11:44:29

ZHero wrote:

hey! sure?

Mathworld:

A Smith number is a composite number the sum of whose digits is the sum of the digits of its prime factors (excluding 1). (The primes are excluded since they trivially satisfy this condition). One example of a Smith number is the beast number

666 = 2*3*3*37

since

6+6+6 = 2+3+3+(3+7) = 18

Then there are the Smith relatives, which are consecutive numbers that are also Smith numbers :
Smith brothers: eg, 728, 729
Smith triples: eg, 73615,73616,73617
Smith quads: eg, 4463535, 4463536, 4463537, 4463538
...etc.

Of course, the term 'Smith brothers' is not strictly correct, because, according to this article by that prolific writer, Anon Y. Mous, "all odd numbers are 'masculine' and all even numbers 'feminine' ", meaning that consecutive number gender alternates.

ZHero wrote:

the First Letter of my name is "M" (the 13th Letter) and the First 4 (=1+3) Letters are "mith"

So you're related to the Smith family too?! Though distantly, as it seems to be in name only. smile

3757

3757 occurs at position 511 of concatenated consecutive Smith triangular numbers, whose string commences with the first such number.

AND, even furthermore still(!)......3757-511=3246 (ie, 2*3*541), which is also a Smith number:
3+2+4+6 = 2+3+5+4+1 = 15

#3179 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-28 04:16:11

up, Bobby. I don't check them all...just some sometimes. I don't know what the last two mean, but I've worked out how to check the others. The second and third constants had me stumped for a while.

3692

3 June 1992 converts to 33758 in Excel 'date-time code'.

3+3+7 = 13, and 5 + 8 = 13.

#3180 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-28 03:58:58

Hi Bobby,

Your 3497 position at 12878 was correct, so you must have put in that same number again into your program instead of 3549. Anyway, 12878 + (3549-3497)*4 = 13086, not 13085.

I'll skip this round...to keep pace with the post# x 13 'rule'.

ZHero wrote:

First occurrence of Devil's number 666 hence is a 3D number tongue

666 is also a 'Smith' number, and if the letters of that name are ascribed a value corresponding to their position in the alphabet (ie, a=1, b=2......z=26), the sum of those values is 69, which is a right or left 180° rotatable number.

#3181 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-28 03:41:50

3601
3614
3627

3627...36 & 27: the first occurrence of consecutive multiples of 9 so far.

And 36 - 27 = 9!!!

#3182 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-28 03:25:50

3562

This is post #274

2 + 7 + 4 = 13....and 3562/13 = 274.

Btw, Bobby,  3549 occurs at position 13086 in Champernowne's number.

#3183 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-28 03:18:30

3536

ie, consecutive pairs.

The only other consecutive pairs so far appear in the number 2223.

3536 - 2223 = 1313 (a very significant pair!)

The sum of the digits of 3536 and 2223 is 26, which is 13 + 13...ie, another pair of 13s.

#3184 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-28 03:02:06

3510

ie, the 3rd of May this year.

Deduct today (28 April) = 5 days...and 3*5-10 = 5.

#3185 Re: Puzzles and Games » Longest last-letter sentence » 2010-04-27 10:25:22

Once everything goes, suddenly you understand
- dreams;
- surreal life energy;
- youth's surprisingly-yobbish, heartache-evoking, gestalt therapy yackety-yack;
- know-it-all, letter-perfect, terrifying "generals" (slowly, yet turbulently yshent...thence eschewed);
- DNA and DVDs;
- stacked data arrays' structure

#3186 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-27 02:51:18

bobbym wrote:

3419....The 6624 th digit of Champernowne's number.

I counted 3419 to be the first four digits after the 6628th....but near the end I ran out of hairs on my arms that I was using to help me with the counting, so I might be wrong.

3432: 3*4+3-2 = 13

#3187 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-27 01:40:10

Btw, Bobby, has the world famous Palazzo Hotel moved from its 3325 location? I don't know how your numbering is over there, but does that mean it's now across the road from where it was, and has taken over the spot previously occupied by the world famous Table 10 restaurant?

3406: 3 + 4 + 0 + 6 = 13

#3188 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-27 01:31:53

Hi Bobby,

I only got my 3354 in before you because, unlike you who slogged away at your construction, I just cut and pasted the info. I feel like a real heel! sad

3367: 3 - 3 + 6 + 7 = 13

3380: The 3380.net domain is available for purchase. This is a great chance for anyone wanting a domain name bearing a number that features so prominently on MIF!

#3189 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-27 01:11:08

ZHero wrote:

i mentioned that in #225

I was just making the numbers catch up to the unwritten 'rule' that post# x 13 = number, which we didn't do back then.

3354

"3354 McNair" is a main belt asteroid with an orbital period of 1294.8501472 days (3.55 years).

The asteroid was discovered on February 8, 1984, and is named in memory of Ronald McNair, one of the astronauts who died in the 1986 Challenger space shuttle disaster.

#3190 Re: Puzzles and Games » Longest last-letter sentence » 2010-04-27 00:21:53

Once everything goes, suddenly you understand
- dreams;
- surreal life energy;
- youth's surprisingly-yobbish, heartache-evoking, gestalt therapy yackety-yack;
- know-it-all, letter-perfect, terrifying "generals" (slowly, yet turbulently yshent...thence eschewed);
- DNA and DVDs;
- stacked data

#3191 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-04-26 23:25:00

We lost a number in posts #223/#224.

3302 - Postcode of Branxholme in south-western Victoria, Australia.

3315 - Postcode of Coleraine, which is on the Glenelg Highway about 40 kms nearly directly north of Branxholme.

#3192 Re: Exercises » What do you think? » 2010-04-26 11:06:20

Hi Bobby,

Aah, I see.

I never learnt about dividing polynomials. Anyway, I worked my way to your answer with MIF's help.

Looks like I didn't interpret "remainder" correctly as applied to polynomial division...although I think it stands up mathematically when applying x = 30 to my polynomial and the divisors.

MIF says: "just put the remainder divided by the bottom polynomial as part of the answer", and so my answer becomes x + 36 + 346/(x-9).

For x = 30, 346/(x-9) is 16 remainder 10, and so still agrees with my misinterpreted understanding of "remainder".

That puts a whole new light onto your problem. Not sure if I can manage to solve it now.

#3193 Re: Exercises » What do you think? » 2010-04-26 10:06:23

bobbym wrote:

When you divide your answer by (x-9) what do you get for a remainder? Is it 10?

I think so

#3195 Re: Exercises » Is this cool with you? » 2010-04-25 17:50:17

Sorry...that's too advanced for me. I never did any of that at school (up to 4th-year high is my limit).

#3196 Re: Exercises » Is this cool with you? » 2010-04-25 17:35:47

bobbym wrote:

The answer is suggestive.

Something to do with Octal (the number after 8 is 11) or binary (255 = 11111111), maybe?

#3198 Re: Exercises » Is this cool with you? » 2010-04-25 16:32:06

bobbym wrote:

Do you have some idea in mind?

I tried my longhand idea...and I was wrong. Too much mental arithmetic involved, and too easy to make a mistake. Also too easy to miss some. It can be done...with some sweat and tears (unless you're wide awake for this sort of thing).

I had another idea in mind, but that is a bit tricky too and involves quite a few additions. I think my original idea with LB, which was quite easy to set up and solves quickly, is my best option so far.

Btw, is my answer correct?

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