Number sequence

[ClarkyT]

13,12,13,16,12,20,12,?

2,3,4,9,8,27,?


Any help with these very much appreciated with an explanation

Thanks

[Ladymuck]

They look like 2 alternating sequences

So the first one is

13, 12, 13, 16, 12, 20, 12,

So the underlined sequence goes up by adding 4 each time. The bold sequence goes down by 1 every 2nd time.

Similarly

2, 3, 4, 9, 8, 27

The bold numbers multiply by 2 each time, the italic numbers multiply by 3 each time.

[ClarkyT]

Thanks very much