Summary from Goodreads:
Laureth Peak's father has taught her to look for recurring events, patterns, and numbers - a skill at which she's remarkably talented. When he goes missing while researching coincidence for a new book, Laureth and her younger brother fly from London to New York and must unravel a series of cryptic messages to find him. The complication: Laureth is blind. Reliant on her other senses and on her brother to survive, Laureth finds that rescuing her father will take all her skill at spotting the extraordinary, and sometimes dangerous, connections in a world full of darkness.