4
$\begingroup$

Replace the question mark and explain the rule behind this sequence:

5, 12, 24, 36, 52, 68, 84, 100, ?

$\endgroup$
1

2 Answers 2

4
$\begingroup$

The next term is:

120

Because the terms are all:

The sum of the next 2 consecutive prime numbers:

2+3=5,
5+7=12,
11+13=24,
17+19=36,
23+29=52,
31+37=68,
41+43=84,
47+53=100

Meaning that the next term must be:

59+61=120

$\endgroup$
3
  • $\begingroup$ I feel like this question is a duplicate of an existing one, but a quick search before posting did not reveal an appropriate question... Happy to stand corrected if anybody finds one! :) $\endgroup$
    – Stiv
    Dec 1, 2019 at 12:11
  • $\begingroup$ Yes, 120 is correct. I think you might refer to my previous post which also consisted of prime numbers. They were similar but not the same. $\endgroup$ Dec 1, 2019 at 12:27
  • $\begingroup$ @Prim3numbah That may be it - the multiplication one... $\endgroup$
    – Stiv
    Dec 1, 2019 at 12:28
0
$\begingroup$

119? With regard to the main increase amount (ie 7, 12, 16), change of +5 then 0 repeated x 1, change of +4 then 0 repeated x 3, change of 3 then 0 repeated x 5. With the zero repetition being increasing odd numbers and the main increasing amount reducing by 1 each round.

$\endgroup$
1
  • $\begingroup$ I see. But no, its not correct. $\endgroup$ Dec 1, 2019 at 11:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.