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A180490 Numbers n such that (A000120(n))^2 divides n. 2
1, 2, 4, 8, 12, 16, 20, 24, 32, 36, 40, 48, 64, 68, 72, 80, 81, 96, 128, 132, 136, 144, 160, 162, 192, 240, 252, 256, 260, 261, 264, 272, 288, 320, 324, 368, 384, 425, 432, 464, 480, 504, 512, 516, 520, 522, 528, 544, 576, 624, 625, 637, 640, 648, 675, 688, 720 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

This is a subsequence of A049445.

LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..10000

FORMULA

{n: (A000120(n))^2 | n}.

MATHEMATICA

fQ[n_] := Divisible[ n, DigitCount[n, 2, 1]^2]; Select[ Range@ 735, fQ] (* Robert G. Wilson v, Sep 10 2010 *)

CROSSREFS

Cf. A049445.

Sequence in context: A048166 A335738 A010066 * A160408 A221707 A186146

Adjacent sequences:  A180487 A180488 A180489 * A180491 A180492 A180493

KEYWORD

easy,nonn

AUTHOR

Ctibor O. Zizka, Sep 08 2010

EXTENSIONS

a(43) onwards from Robert G. Wilson v, Sep 10 2010

STATUS

approved

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Last modified August 6 08:39 EDT 2020. Contains 336228 sequences. (Running on oeis4.)