What’s the next number in the sequence?

$4, 6, 12, 18, 30, ?$

This one is pretty easy, so I will post the answer in a few days if no one gets it.


1 Answer 1


Is it:

42. The twin primes are $(3,5), (5,7), (11,13), (17,19), (29,31), (41,43), \dots$. Sum each pair and divide by two gives $4,6,12,18,30,42,\dots$.


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