| Title: | Mathematics at DEC |
| Moderator: | RUSURE::EDP |
| Created: | Mon Feb 03 1986 |
| Last Modified: | Fri Jun 06 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2083 |
| Total number of notes: | 14613 |
What are the next terms in the following series?
36 91 21 51 82 12
and
18 22 26 21
The latter is said to be temporal.
I'm useless at this sort of thing, can anyone give some good stratagies
for solving these?
Thanks
Tony.
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 1047.1 | series depending on first number??? | AISG::MONROE | Tue Apr 04 1989 12:15 | 31 | |
Well, I have worked with these type of problems a little so I'll
take a crack at this.
For the first series...
>> 36 91 21 51 82 12
my guess would be that it would continue with
42 73 03 33 64 ...
It seem to add 30 (hence the 3 in 36), mod with 100. When the digits
of a number add up to 6 (hence the 6 in 36), we shift increment
the one's digit.
For the second series...
>> 18 22 26 21
my guess is to continue it with ...
25 29 33 27 41 45 49 53 51 ...
Here we add 4 to the previous number until the sum of the digits
add up to 8 (hence the 8 in 18). When the digits to add up to 8,
we set the one's digit to 1 (hence the 1 in 18). This will lead
to a problem though if the number 71 ever shows up in the series.
As I said earlier, I've had a "little" practice with these. I'd
be glad to see what other possibilities other people come up with.
-Tod-
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| 1047.2 | turn it on it's head | NEATO::CAMHI | Tue Apr 04 1989 15:16 | 36 | |
a short version of the solution for
a. 36 91 21 51 82 12
comes when you look at it slightly differently (it also explains the
36):
push the numbers together:
b. 369121518212
which, when pulled back apart slightly differently gives:
c. 3,6,9,12,15,18,21,2...
so you'd continue (b) with:
d. 42730333639424548...
so you'd get the solution:
e. 42,73,03,33,63,94,24,54...
which gives you the same solution as .1
where they would possibly diverge is once (c) gets to 3-digit numbers;
since the series (a) is combining everything into 2-digits, (e)
would continue:
...9 1,02, 10,5 1,08, 11,1 1,14...
but .1 may do something funny.
-Keith
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| 1047.3 | NEATO::CAMHI | Tue Apr 04 1989 16:57 | 8 | ||
in case it wasn't clear what I was doing in .2, its just a series
of multiples of 3 squooshed together then pulled out in 2-digit
numbers
re .0
what is meant by "temporal" with regard to series?
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| 1047.4 | HERON::BUCHANAN | Andrew @vbo DTN 828-5805 | Wed Apr 05 1989 13:22 | 7 | |
Good on you for solving No.1 "temporal" means "related to the concept of 'time'" Eg the four numbers given might be days of the month, or something. Andrew. | |||||