Number Bubbles

Put the numbers

1, 2, 3, 4, 5, 6, 7, 8, 9

in the bubbles so that each edge adds up to the same thing.

What number comes next?

1, 3, 6, 10, 15, 21, ___

Ancestrally speaking

Hungry Horace was looking through the family photo album, which has a photo of each of his parents, each of his grandparents all the way up to each of his great-great-great grandparents. How many photos is that?

Welcome!

Welcome to our new Killygarry Maths blog. Come here regularly for tutorials, games, puzzles, competitions and more!
We'll be putting up weekly brain teasers and whoever solves them first will get the school maths award.

Here's the first one:

Why are some letters above the line and some below it? It's logics, not maths.
Post your answer as a comment. First one correct gets the first ever School Maths Award.