A088382 Numbers not exceeding the 4th power of their smallest prime factor.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 89, 91, 95, 97, 101, 103, 107, 109, 113, 115, 119, 121, 125, 127, 131, 133

Offset: 1

Author

Reinhard Zumkeller, Sep 28 2003

Keywords

• nonn

Comments

a(n) <= A020639(a(n))^4 = A088379(a(n)); complement of A088383;

a(n) < A088383(k) for n <= 67, a(n) > A088383(k) for n > 67.

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A088380, A000430, A020639, A088379, A088383.

Positions of numbers less than 5 in A307908.

Programs

Haskell

a088382 n = a088382_list !! (n-1)
a088382_list = [x | x <- [1..], x <= a020639 x ^ 4]
-- Reinhard Zumkeller, Feb 06 2015

Mathematica

Select[Range[200],#<=FactorInteger[#][[1,1]]^4&] (* Harvey P. Dale, Jan 25 2015 *)