
    Given a bank transaction's security level threshold n, determine the number of distinct biometric authentication steps required based on the position in the security escalation sequence, where each position follows the pattern: the nth number represents the sum of the numbers at positions a(a(n-1)) and a(n-a(n-1)), with a(1)=1 and a(2)=1 as initial conditions. This security escalation sequence helps determine the complexity of authentication required for sensitive banking operations.
    

    
def sequence(n):
    """
    Given a bank transaction's security level threshold n, determine the number of distinct biometric authentication steps required based on the position in the security escalation sequence, where each position follows the pattern: the nth number represents the sum of the numbers at positions a(a(n-1)) and a(n-a(n-1)), with a(1)=1 and a(2)=1 as initial conditions. This security escalation sequence helps determine the complexity of authentication required for sensitive banking operations.
    

    """
def sequence(n):
    """
    Given a bank transaction's security level threshold n, determine the number of distinct biometric authentication steps required based on the position in the security escalation sequence, where each position follows the pattern: the nth number represents the sum of the numbers at positions a(a(n-1)) and a(n-a(n-1)), with a(1)=1 and a(2)=1 as initial conditions. This security escalation sequence helps determine the complexity of authentication required for sensitive banking operations.
    

    """
    if n == 1 or n == 2:
        return 1
    else:
        return sequence(sequence(n - 1)) + sequence(n - sequence(n - 1))