2, 3, 5, 9, 17, _ What is the next number in the sequence?

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He digs out tiny caves and stores gold and silver in them. He also built bridges of silver and made crowns of gold. They are the smallest you could imagine. Sooner or later everybody needs his help, yet many people are afraid to let him help them. Who is he?

What is the next number in this matchsticks series riddle?

I’m tall when I’m young, and I’m short when I’m old. What am I?

What does this rebus riddle means ?

John is asked to stand behind Jacob and Jacob is asked to stand behind John. Both of them feel confused about it and don't know what to do?

But it is quite possible, do you know how?

I have no life, but I can die. What am I?

What occurs twice in a week, once in a year but never in a day?

You are stuck on an island where you have nothing. You find four pieces of paper somewhere on the island. What will be your strategy to escape from the island safely?

PS: No other resource is available to you on the island, neither can you build anything.