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A118669
Numbers that are not squarefree, but contain their squarefree kernel in decimal representation.
1
25, 32, 36, 96, 100, 125, 128, 162, 216, 243, 256, 300, 486, 512, 576, 625, 648, 700, 768, 864, 1000, 1024, 1100, 1215, 1296, 1300, 1536, 1700, 1900, 2048, 2100, 2300, 2430, 2900, 2916, 3000, 3100, 3125, 3300, 3456, 3700, 3773, 3900, 4100, 4300, 4608
OFFSET
1,1
COMMENTS
For k>1: m*10^k are terms for squarefree numbers m coprime to 10.
If m is a term and coprime to 10 then also 10*m is a term.
LINKS
Eric Weisstein's World of Mathematics, Squarefree.
MATHEMATICA
Select[Range[5000], (r = rad[#]) < # && SequenceCount @@ IntegerDigits[{#, r}] > 0 &] (* Amiram Eldar, Sep 07 2020 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, May 19 2006
STATUS
approved