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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 (list; graph; refs; listen; history; text; internal format)
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

Amiram Eldar, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Squarefree.

MATHEMATICA

Select[Range[5000], (r = rad[#]) < # && SequenceCount @@ IntegerDigits[{#, r}] > 0 &] (* Amiram Eldar, Sep 07 2020 *)

CROSSREFS

Cf. A005117, A013929, A007947, A076333.

Sequence in context: A043146 A043926 A202000 * A092100 A172007 A107258

Adjacent sequences:  A118666 A118667 A118668 * A118670 A118671 A118672

KEYWORD

nonn,base

AUTHOR

Reinhard Zumkeller, May 19 2006

STATUS

approved

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Last modified July 1 09:41 EDT 2022. Contains 354958 sequences. (Running on oeis4.)