Please explain this maths question?

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My son (10) assures me it's perfectly simple and the answer is 122 but I've no idea whether he's right or if so why so if he's wrong I can't even correct him I'm mortified that I can't do a question aimed at a 10 year old - maths was never my strong point.. but I'm clearly worse than I thought. Actually feeling quite rubbish about it so please be kind to me.

Find the next number in this sequence

2, 5 , 14, 41

Have you asked him why he thinks that number is right?

If you double the number then add on one less.

so 41 x 2 = 82, then add on 40 ☺️

You add 3, 3 Squared, 3 cubed etc, 3 to the power of 4 etc

to get to the next number in the sequence you multiply by 3 then take away 1, so 122 would be correct

(2 x 3) - 1 = 5
(5 x 3) - 1 = 14
(14 x 3) - 1 = 41
(41 x 3) - 1 = 122

He's correct 😁

He muttered something about the 9 times table, told me I wouldn't understand anyway and wandered off to bounce on the trampoline.

Now sitting here feeling rubbish :(

2 plus 2 plus 2 is 6 minus 1 is 5
5 plus 5 plus 5 is 15 minus 1 is 14
41 plus 41 plus 41 is 123 minus 1 is 122

It looks like maybe he is multiplying the difference in previous numbers by 3?

So 2+3 = 5
then 5 + (3x3) = 14
then 14 + (3x9) = 41
then 41 + (3x27) = 122

Yeah it's x3-1

I have always found these ridiculously difficult. I think I must have missed that week at school 😂

2 (+3¹ or 3=) 5 (+3² or 9 =)14 (+3³, or 27 =) 41 (+3⁴ or 81=) 122
Hope that makes sense

Thanks everyone - apparently number patterns are "really good fun".

I blame DP he did not inherit this from me

@AppleKatie You've made me feel better that I'm not alone - it's rather embarrassing really and the trouble is that I'm beginning to feel like I missed most weeks of maths at school.

DD's just done GCSEs and to be honest the majority of the maths, chemistry and physics was absolute gobbledygook as far as I was concerned. She wants to do them for A Level, so that's me finished!

Yes, this makes complete sense and is where I got.

Everyone trying to explain just complex equations, no thanks. Why do you have to complicate if?

It's about spotting patterns. It's probably not something you can learn quickly, like the 10 x table. You need a knack for it and practice/experience.

Who used complex equations?

I do it this was:
difference between 2 and 5 = 3
3x3=9, then 9 + 5 =14
multiply 9 by 3 = 27
then 14 + 27 = 41
multiply 27 by 3 = 81
then 41+ 81 = 122
He's right

I'm a fully grown woman trying to pass my maths GCSE and I can promise you that desire being in the top set at school and dropping out in year 10, I do not remember ANYTHING past basic 56x4 type multiplication. Never mind trying to get the information on number patterns to stick in my brain. At least 3 times a week I'll spend an hour on or and think YES! I've got it! But two days later I'm back at the beginning mouth and finger reading the instructions. Oddly though, I remember graphs and coordinates really well? Angles are okish as are fractions. But covering fractions to decimals? Jog on !

Yes it’s this.

When doing sequences, the easiest method is to find the difference between the numbers, then see what the pattern is. In this case the difference is:

3, 9, 27

— which are all multiples of 3 (the child should recognise this from times tables). The next figure is 27x3 so you add 81 to the original sequence to get 122.

The trick with sequences is to keep looking at the differences between the numbers (and turning these into a new sequence), until you spot an obvious pattern: then work back to the original sequence by adding the next term in the pattern.

Ask him to see if he could work out what the nth term formula would be....

That might blow his mind.

Your son is correct.
multiply the number by 3 and subtract 1
2x3 = 6 - 1 = 5
5x3 = 15 - 1 = 14
14x3 = 42 - 1 = 41
41x3 = 123 - 1 =122