196651domain: NAppears in sequencesa(n) = round(n*phi^20), where phi is the golden ratio, A001622.at n=13A004955a(n) = ceiling(n*phi^20), where phi is the golden ratio, A001622.at n=13A004975Strong pseudoprimes to base 10.at n=25A020236a(n) = Fibonacci(n) + Fibonacci(2n+1).at n=13A087124