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Fear not the infinity of the truth. One inch closer we move towards it, one inch of delight we shall receive from it.

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Test

[001] Twice linear

Description: Consider a sequence u where u is defined as follows:

The number u(0) = 1 is the first one in u. For each x in u, then y = 2 * x + 1 and z = 3 * x + 1 must be in u too. There are no other numbers in u. Ex: u = [1, 3, 4, 7, 9, 10, 13, 15, 19, 21, 22, 27, …]

1 gives 3 and 4, then 3 gives 7 and 10, 4 gives 9 and 13, then 7 gives 15 and 22 and so on…

Task: Given parameter n the function dbl_linear (or dblLinear…) returns the element u(n) of the ordered (with <) sequence u (so, there are no duplicates).

Example: dbl_linear(10) should return 22

Note: Focus attention on efficiency

#!/usr/bin/python
import re

line = "Cats are smarter than dogs"

matchObj = re.match( r'(.*) are (.*?) .*', line, re.M|re.I)

if matchObj:
    print "matchObj.group() : ", matchObj.group()
    print "matchObj.group(1) : ", matchObj.group(1)
    print "matchObj.group(2) : ", matchObj.group(2)
else:
    print "No match!!"