Well met with Fibonacci bigger brother, AKA Tribonacci.
As the name may already reveal, it works basically like a Fibonacci, but summing the last 3 (instead of 2) numbers of the sequence to generate the next. And, worse part of it, regrettably I won't get to hear non-native Italian speakers trying to pronounce it :(
So, if we are to start our Tribonacci sequence with [1, 1, 1]
as a starting input (AKA signature), we have this sequence:
[1, 1 ,1, 3, 5, 9, 17, 31, ...]