Hello everyone,
It has been time TI-Planet have not organized a contest, and here is the lack filled
So we organize a contest, about 5 weeks, well mixing arithmetic and algorithmics.
Introduction:In mathematics, a
prime palindom number is a number which is both prime and palindromic.
A
prime number is an integer that only admits two positive and integer divisors (which are 1 and itself).
This definition excludes 1, which has only one positive and integer divisor ; it excludes 0 too, which is divisible by all the positive integers.
For example 6 = 2 × 3 is not prime and 21 = 3 × 7 or 7 × 3 either. But 11 is prime because 1 and 11 are the only divisors of 11.
So, the prime numbers are, in order, 2, 3, 5, 7, 11...
A
palindromic number is a number whose writing (in base 10) is read in the same way from left to right and from right to left.
For example, all the 1-digit numbers are palindromic: 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9.
The 2-digit palindroms are: 11, 22, 33, 44, 55, 66, 77, 88 and 99.
101 is a 3-digit palindromic number.
So, the
prime palindromic numbers are: 2, 3, 5, 7, 11, 101, 131...
Subject : Make a program fastest as possible to find the n-th prime palindromic number.
Plateform : The candidate will perform its participation:
- TI-Nspire
- TI-82Stats/83/76
- TI-83+/84
Categories:The candidate's production will be judged in one of those categories:
- TI-Nspire
- TI-82Stats/83/84/76
Languages : - TI-Basic Nspire
- TI-Basic TI-82Stats/83/84/76
- TI-83+/84 Assembly NO SHELL (So, you can participate with Axe compiled for no shell)
- TI-82Stats/83/76 Assembly NO SHELL
NB: on TI-82Stats/83/84,TI-Basic and assembly combinations are allowed.
Constraints : On TI-82Stats/83/84/76, the program will catch n in the 'Ans' variable, and will send the nth prime palindromic number as a result in Ans.
For example, to obtain the 42th prime, we will type:
- TI-Basic program: 42:prgmPALPREM
- TI-83+/84 Assembly program: 42:Asm(prgmPALPREM
- TI-82Stats/83/76 Assembly program: 42:Send(9prgmPALPREM
In each case, the program should send the result 18181 in Ans, reusable in the home screen for calculations.
On TI-Nspire, the main program should be a function which take the n parameter and which sends the result. For example, palprem(42) should answer 18181.
YOU MUST NOT USE a pre-calculated list of prime palindromic numbers in your program, directly under penalty of disqualification.
YOU MUST NOT USE functions like isPrime() which would provide a direct response, it destroys the value of algorithmic thinking, and it would be unfair to those who don't have this function... ;)
The program MUST run on not-CAS TI-Nspires.
Notation : The final score will be on 20 points, and the scale is as follows:
- 3 points for the proper functioning of the program
- 10 points for the fast execution of the program (it will be tested and compared to competitors on identical machines with identical languages)
- 3 points for the respect of the rules
- 4 points for an explanation
Jury : Participations are rated on an equitable basis according to a common scale by a jury whose composition is as follows:
- Adriweb
- Critor
- Laurae
- Levak
- Lionel Debroux
When ? : The contest starts Monday the 1st of April 2013 and finishs Sunday the 12th of May, 23h59 (GMT+1)
How ? : To participate, candidates must send to the email address
[email protected] :
- complete mailing address with first and last name
- a valid email address for contact
- the expected production (8xp, 83p, tns)
- any other information or file deemed useful by the candidate concerning its production
The e-mail correctly send is taken as an entry.
Lots : Through our partnership with TI-France and Jarrety, the winners of the contest (one winner per category) will be rewarded with:
- 1st price: 1 calculator + 4 TI-Planet stickers
- 2nd price: 1 poster TI + 3 TI-Planet stickers
- 3rd price: 2 TI-Planet stickers
1st price in the Nspire category: a TI-Nspire CX (not CAS)
1st price in the TI-82/83/84 category : a TI-84 Pocket.fr
Complete rules: The complete rules for this contest, legally registered to an usher, are available on
TI-Planet or
the UPECS website. (French)
See you soon on TI-Planet !
PS: I know I'm a bit late, because the contest has started...
