euler001.py

"""
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9.

The sum of these multiples is 23.

Find the sum of all the multiples of 3 or 5 below 1000.
"""


def main():
    # input number of test cases
    t = int(raw_input().strip())
    # for each case, compute the sum
    for _ in range(t):
        # input of n as a long integer to deal with big numbers
        n = long(raw_input().strip())
        # find the number of multiples within [0, n)
        m3 = (n - 1) / 3
        m5 = (n - 1) / 5
        m15 = (n - 1) / 15
        # compute directly the sum of these multiples
        print (3 * m3 * (m3 + 1) + 5 * m5 * (m5 + 1) - 15 * m15 * (m15 + 1)) / 2

if __name__ == '__main__':
    # print "This program is being run by itself"
    main()
else:
    print 'I am being imported from another module'