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Primevens and primeodds (Posted on 2016-01-10) Difficulty: 4 of 5
Let a primeven be a positive integer that is the product of an even number of primes. Let a primeodd be a positive integer that is the product of an odd number of primes. Then, 1 is a primeven because it is the product of 0 primes. 2 is a primeodd because it is the product of 1 prime. 3 is a primeodd because it is the product of 1 prime. 4 is a primeven because it is the product of 2 primes. Here are the first 10 positive integers.
Number:   Factorization:      Number of primes:   Type:
1                             0                   primeven
2         2                   1                   primeodd
3         3                   1                   primeodd
4         2*2                 2                   primeven
5         5                   1                   primeodd
6         2*3                 2                   primeven
7         7                   1                   primeodd
8         2*2*2               3                   primeodd
9         3*3                 2                   primeven
10        2*5                 2                   primeven
Suppose the primevens and primeodds had a race. First, the primevens would be ahead because 1 is a primeven. Then, there would be a tie because 2 is a primeodd. Then, the primeodds would be ahead because 3 is a primeodd. Then, there would be a tie because 4 is a primeven. Here are the winners from 1 to 10.
Number:   Type:          Primevens:     Primeodds:     Winner:
1         primeven       1              0              primevens
2         primeodd       1              1              tie
3         primeodd       1              2              primeodds
4         primeven       2              2              tie
5         primeodd       2              3              primeodds
6         primeven       3              3              tie
7         primeodd       3              4              primeodds
8         primeodd       3              5              primeodds
9         primeven       4              5              primeodds
10        primeven       5              5              tie
The primevens were ahead at the start, but have not been ahead since then. Do the primevens ever become the winner again?

  Submitted by Math Man    
Rating: 4.0000 (1 votes)
Solution: (Hide)
Yes. The primevens are ahead at 906150257.

Comments: ( You must be logged in to post comments.)
  Subject Author Date
Some ThoughtsOEIS sequencesBrian Smith2016-01-12 11:23:22
re(5): some stats extendedbroll2016-01-11 23:15:22
Solutionre(4): some stats extendedCharlie2016-01-11 22:06:41
re(3): some stats extendedCharlie2016-01-11 07:39:15
re(2): some stats extendedJer2016-01-10 20:18:57
re: some stats extendedCharlie2016-01-10 17:56:21
Some Thoughtssome statsCharlie2016-01-10 14:12:52
Some Thoughtssome thoughts.broll2016-01-10 12:30:36
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