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A144976 Nonsquarefree numbers n such that n is divisible by the maximal exponent in the prime factorization of n. 1
4, 12, 16, 18, 20, 24, 27, 28, 36, 44, 48, 50, 52, 54, 60, 68, 72, 76, 80, 84, 90, 92, 98, 100, 108, 112, 116, 120, 124, 126, 132, 135, 140, 144, 148, 150, 156, 160, 164, 168, 172, 176, 180, 188, 189, 192, 196, 198, 204, 208, 212, 216, 220, 228, 234, 236, 240, 242, 244, 252, 256, 260, 264, 268, 270, 272 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

FORMULA

{A013929(i): A051903(A013929(i)) | A013929(i)}. - R. J. Mathar, Oct 24 2008

MAPLE

A051903 := proc(n) local a, ifs, p, e; a := 1 ; max( seq(op(2, p), p=ifactors(n)[2]) ); end: isA013929 := proc(n) RETURN( not isprime(n) and A051903(n) > 1 ) ; end: isA144976 := proc(n) RETURN( isA013929(n) and (n mod A051903(n)) = 0 ); end: for n from 4 to 400 do if isA144976(n) then printf("%d, ", n) ; fi; od: # R. J. Mathar, Oct 24 2008

MATHEMATICA

Select[Range[300], !SquareFreeQ[#]&&Divisible[#, Max[FactorInteger[#][[All, 2]]]]&] (* Harvey P. Dale, Jul 01 2017 *)

CROSSREFS

Cf. A137257.

Sequence in context: A228091 A157849 A137257 * A119622 A280892 A328840

Adjacent sequences:  A144973 A144974 A144975 * A144977 A144978 A144979

KEYWORD

nonn

AUTHOR

Giovanni Teofilatto, Sep 28 2008

EXTENSIONS

Adapted definition, inserted 18, 20 and extended. - R. J. Mathar, Oct 24 2008

STATUS

approved

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Last modified August 6 19:52 EDT 2020. Contains 336256 sequences. (Running on oeis4.)