A088381 Numbers greater than the cube of their smallest prime factor.

10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 33, 34, 36, 38, 39, 40, 42, 44, 45, 46, 48, 50, 51, 52, 54, 56, 57, 58, 60, 62, 63, 64, 66, 68, 69, 70, 72, 74, 75, 76, 78, 80, 81, 82, 84, 86, 87, 88, 90, 92, 93, 94, 96, 98, 99, 100, 102, 104, 105, 106, 108, 110, 111, 112

Offset: 1

Author

Reinhard Zumkeller, Sep 28 2003

Keywords

• nonn

Comments

a(n) > A020639(a(n))^3 = A088378(a(n)); complement of A088380;

a(n) > A088380(k) for n <= 28, a(n) < A088380(k) for n > 28.

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A080257, A088378, A088380, A088383.

Cf. A020639, A138511 (subsequence).

Positions of numbers greater than 3 in A307908.

Programs

Haskell

a088381 n = a088381_list !! (n-1)
a088381_list = filter f [1..] where
                      f x = p ^ 2 < div x p  where p = a020639 x
-- Reinhard Zumkeller, Jan 08 2015

Maple

filter:= n -> n > min(numtheory:-factorset(n))^3:
select(filter, [$2..200]); # Robert Israel, Aug 11 2020

PARI

isok(n) = n > factor(n)[1,1]^3; \\ Michel Marcus, Jan 08 2015