Browse Teasers
Search Teasers

## 31, 3, 5, 11, 23, 13

Series teasers are where you try to complete the sequence of a series of letters, numbers or objects.

 Puzzle ID: #5387 Fun: (2.79) Difficulty: (3.06) Category: Series Submitted By: im_para_noid

Transform the following numbers into a palindromic sequence (one that reads the same backwards as forwards) by applying the same formula to all the numbers. What is the formula and what are the resulting numbers?

31, 3, 5, 11, 23, 13

## What Next?

See another brain teaser just like this one...

Or, just get a random brain teaser

If you become a registered user you can vote on this brain teaser, keep track of
which ones you have seen, and even make your own.

 mollynoodl Jul 25, 2002 Actually, 3 squared is not 9!! SkEwL_gUrl Jul 26, 2002 Actually, 3 squared is 9 george1978 Jul 29, 2002 yes 3 squared is 9 check your calculator 3x3= 9. for a square of a nuber is a number times it self two times ie 3x3. Stargirl Jul 29, 2002 that was a really hard one sillywilly Jul 31, 2002 The key is to identify them as prime numbers. If you pair them in a colums, then you can see the pattern if you're familiar with the squares of primes. hcleong Aug 14, 2002 Er... multiply each number by 0? A_n_d_y Aug 14, 2002 no hcleong, the 2 and 5 would mess that idea up. Although it's interesting that it's nearly a palindrome. zangel3000 Aug 14, 2002 No offense, but I don't think that teaser is that great, but hey, but that's just my oppinion. Lyceum_ Aug 14, 2002 Multiplying by zero does work, and the palindrome becomes 0 0 0 0 0 0. You could also say "for every number equal to 5, subtract 3". That would give the sequence 31 3 2 11 23 13. bearppbj Aug 14, 2002 We have a bunch of brainiacs here. One can't multiply 3 times 3, another can't multiply numbers by 0 and yet another can't spell numbers. I've had a long day, so I'm a bit cranky. bearppbj Aug 14, 2002 Lyceum, the teaser says to apply the same formula to ALL the numbers, not SOME of the numbers. dsquared Aug 15, 2002 Great teaser, very clever, very tough. mpeoples Aug 15, 2002 Multiply each number by zero. It creates a series of zeroes which obviously read that same forward and backward. It's a trick but it's valid. majd Aug 18, 2002 I guessed it rather quickly, nice one. klopper Sep 09, 2002 LOL AT MOLLYNOODL dsquared Sep 10, 2002 Another possibility is to divide each number by itself... another boring answer I know, but it works.... 1,1,1,1,1,1. Just needs a reword to remove these possibilities. It would be good if teasers could be reworded and resubmitted, it would allow for the improvement of many of the teasers on the site. Do you know if this has this been suggested anywhere before Para? jimbo Oct 29, 2003 Excellent puzzle. Extremely interesting to see the relationships generated between primes, squares and palindromes. A lot of concepts happening here. Thanks! griphook Oct 29, 2003 only a 3.09 difficulty rating ? extremely difficult but very creative vbfreak55 Jul 03, 2004 i thought this one was very hard. it was a great idea, though! (user deleted) Jul 03, 2004 i thought that this one was stupid. i didn't know that we could add or multiply the numbers. witness Jul 03, 2004 This one is annoying...not only because it is hard, but because of all the stupid comments like this one. energizer74 Jul 04, 2004 Penguingirl, it says in the instructions to apply a formula to each number. The formula translated (to anybody who knows even a minute amount of math) would be: (31)^2 (3)^2 (5)^2 (11)^2 (23)^2 (13)^2 to get the answer. It took me awhile to figure this one out, and it was a great teaser. cnmne Dec 19, 2004 Sometimes I get lucky. I got this on my second formula (the first was to double each number, which came close). Nonetheless, a clever teaser. Confooseled Oct 05, 2005 ok yeah that was hard.. im kinda Stupid anyways and i stay confused.. and 3 squared is 9!! im not that dumb like sum people Confooseled Oct 05, 2005 it was good tho schatzy228 Dec 01, 2005 WONDERFUL builder May 16, 2011 slick enough for me elentir May 16, 2011 Too many possible answers to this. I went the 'multiply by zero' route as it is the simplest. I like the 'if n=5, n=n-2' formula though. Very creative! dsjt May 16, 2011 I got two other answers... I multiply each number by zero to get 0,0,0,0,0,0 Then I divided each number by itself to get 1,1,1,1,1,1 dsjt May 16, 2011 In MOLLYNOODL's defense she was evidently working in base 8. In that case 3 squared = 10 auntiesis May 17, 2011 Very difficult for me. Wimm Feb 27, 2015 Many solutions possible, as stated earlier. Another one: raise each number to power 0. You get all 1's then, which is a palindrome.