A122145 Numbers k such that q(k) < M(k) where q(k) is the largest prime divisor of k and M(k) is the largest prime power divisor of k.

4, 8, 9, 12, 16, 18, 24, 25, 27, 32, 36, 40, 45, 48, 49, 50, 54, 56, 63, 64, 72, 75, 80, 81, 90, 96, 98, 100, 108, 112, 120, 121, 125, 126, 128, 135, 144, 147, 150, 160, 162, 168, 169, 175, 176, 180, 189, 192, 196, 200, 208, 216, 224, 225, 240, 242, 243, 245, 250

Offset: 1

Author

Douglas Stones (dssto1(AT)student.monash.edu.au), Aug 22 2006

Keywords

• nonn

Links

• Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A006530, A034699, A122144, A122146.

Programs

Mathematica

Select[Range[250], Max[Power @@@ (f = FactorInteger[#])] > f[[-1, 1]] &] (* Amiram Eldar, May 23 2024 *)

PARI

is(n)=my(f=factor(n),k=#f[,1]);for(i=1,k, if(f[i,1]^f[i,2]>f[k,1], return(1)));0 \\ Charles R Greathouse IV, Sep 20 2012

Extensions

Extended by Ray Chandler, Aug 23 2006