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A203662 Achilles number whose largest proper divisor is also an Achilles number. 2
864, 1944, 3888, 4000, 5400, 6912, 9000, 10584, 10800, 10976, 17496, 18000, 21168, 21600, 24696, 25000, 26136, 30375, 31104, 32000, 34992, 36000, 36504, 42336, 42592, 43200, 48600, 49000, 49392, 50000, 52272, 55296, 62208, 62424, 68600, 69984 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Exponent of smallest prime divisor of n is greater than or equal to 3.

Both N and the largest proper divisor of N share the same prime factors with different exponents.

LINKS

Donovan Johnson, Table of n, a(n) for n = 1..1000

EXAMPLE

17496 is in the sequence because 17496=2^3*3^7 (Achilles number) and the largest proper divisor 8748=2^2*3^7 is also an Achilles number.

MATHEMATICA

(* First run the program for A052486 to define achillesQ *) Select[Range[50000], achillesQ[#] && achillesQ[Divisors[#][[-2]]] &] (* Alonso del Arte, Jan 05 2012 *)

CROSSREFS

Cf. A052486, A143610.

Sequence in context: A252305 A252306 A184451 * A179671 A097982 A064321

Adjacent sequences:  A203659 A203660 A203661 * A203663 A203664 A203665

KEYWORD

nonn

AUTHOR

Antonio Roldán, Jan 04 2012

STATUS

approved

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Last modified July 22 03:22 EDT 2017. Contains 289648 sequences.