Function solana_libra_types::proof::treebits::children_from_level

pub fn children_from_level(level: u32) -> u64

Returns the number of children a node level nodes high in a perfect binary tree has.

Recursively,

children_from_level(0) = 0 children_from_level(n) = 2 * (1 + children(n-1))

But expanding the series this can be computed non-recursively sum 2^n, n=1 to x = 2^(x+1) - 2