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 A087133 Number of divisors of n that are not greater than the greatest prime-factor of n; a(1)=1. 2
 1, 2, 2, 2, 2, 3, 2, 2, 2, 3, 2, 3, 2, 3, 3, 2, 2, 3, 2, 4, 3, 3, 2, 3, 2, 3, 2, 4, 2, 4, 2, 2, 3, 3, 3, 3, 2, 3, 3, 4, 2, 5, 2, 4, 3, 3, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 3, 2, 5, 2, 3, 3, 2, 3, 5, 2, 4, 3, 4, 2, 3, 2, 3, 3, 4, 3, 5, 2, 4, 2, 3, 2, 6, 3, 3, 3, 5, 2, 4, 3, 4, 3, 3, 3, 3, 2, 3, 4, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(n)<=A000005(n), a(n)=A000005(n) iff n is prime or n=1; a(n)=2 iff n>1 is a prime power (A000961); a(A087134(n))=n and a(k)

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Last modified August 18 00:28 EDT 2018. Contains 313817 sequences. (Running on oeis4.)