
    At a networking event venue, social spaces are arranged in expanding decagonal patterns to optimize attendee interactions, where each subsequent arrangement accommodates more people than the last. Given a specific arrangement number n, determine the total number of attendees that can be optimally positioned in that particular decagonal social configuration.
    

    
def is_num_decagonal(n):
    """
    At a networking event venue, social spaces are arranged in expanding decagonal patterns to optimize attendee interactions, where each subsequent arrangement accommodates more people than the last. Given a specific arrangement number n, determine the total number of attendees that can be optimally positioned in that particular decagonal social configuration.
    

    """
def is_num_decagonal(n):
    """
    At a networking event venue, social spaces are arranged in expanding decagonal patterns to optimize attendee interactions, where each subsequent arrangement accommodates more people than the last. Given a specific arrangement number n, determine the total number of attendees that can be optimally positioned in that particular decagonal social configuration.
    

    """
    return 4 * n * n - 3 * n