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A260048
Composites whose prime factorization in base 4 is an anagram of the number in base 4.
11
25, 637, 722, 1135, 1243, 1519, 1639, 1734, 1863, 2167, 4735, 4855, 4939, 5311, 5746, 5886, 5967, 6381, 6589, 6713, 7003, 7339, 7407, 7774, 8154, 8503, 8667, 8703, 9457, 11123, 11221, 11711, 15471, 16735, 17779, 17965, 18079, 18283, 18477, 18589
OFFSET
1,1
LINKS
EXAMPLE
25 = 5^2. In base 4, 121 = 11^2.
MATHEMATICA
Select[Range[10^6], !PrimeQ[#] && Sort@ IntegerDigits[#, 4] == Sort@ Flatten@ IntegerDigits[ Select[ Flatten@ FactorInteger@ #, #>1 &], 4] &] (* Giovanni Resta, Jul 14 2015 *)
KEYWORD
base,easy,nonn
AUTHOR
Stephen Tucker, Jul 14 2015
STATUS
approved