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A165714
Let the prime factorization of m be m = product p(m,k)^b(m,k), where p(m,j)<p(m,j+1) for all j, the p's are the distinct primes dividing m, and each b is a positive integer. Then a(n) = product_k {p(A165713(n), k)^b(n,k)}.
1
3, 2, 25, 7, 10, 2, 27, 121, 6, 13, 28, 2, 15, 6, 83521, 19, 50, 23, 63, 22, 6, 5, 104, 9, 14, 24389, 99, 31, 42, 2, 69343957, 34, 35, 6, 1444, 41, 39, 10, 88, 43, 30, 47, 45, 92, 6, 7, 80, 2809, 867, 26, 12, 59, 6655, 14, 513, 58, 62, 61, 132, 2, 21, 325, 90458382169, 34
OFFSET
2,1
COMMENTS
A165713(n) = the smallest integer > n that is divisible by exactly the same number of distinct primes as n is.
EXAMPLE
12 = 2^2 * 3^1, which is divisible by 2 distinct primes. The next larger integer divisible by exactly 2 distinct primes is 14 = 2^1 * 7^1. Taking the primes from the factorization of 14 and the exponents from the factorization of 12, we have a(12) = 2^2 * 7^1 = 28.
CROSSREFS
Sequence in context: A151475 A105525 A228772 * A090883 A100645 A132960
KEYWORD
nonn
AUTHOR
Leroy Quet, Sep 24 2009
EXTENSIONS
Extended by Ray Chandler, Mar 12 2010
STATUS
approved