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Search: id:A075810
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| A075810 |
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Palindromic odd squarefree numbers with an even number of distinct prime factors. |
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+0
1
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| 1, 33, 55, 77, 111, 141, 161, 303, 323, 393, 505, 515, 535, 545, 565, 707, 717, 737, 767, 939, 949, 959, 979, 989, 1111, 1441, 1661, 1991, 3003, 3113, 3223, 3443, 3883, 5005, 5115, 7117, 7447, 7997, 9119, 9229, 9449, 10001, 10101, 10401, 10801, 10901
(list; graph; listen)
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OFFSET
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1,2
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EXAMPLE
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77=7*11 and 3003=3*7*11*13 are palindromic, odd, squarefree, and have an even number of prime factors.
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MAPLE
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test := proc(n) local d; d := convert(n, base, 10); return ListTools[Reverse](d)=d and numtheory[mobius](n)=1; end; a := []; for n from 1 to 11000 by 2 do if test(n) then a := [op(a), n]; end; od; a;
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CROSSREFS
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Cf. A056913.
Sequence in context: A007373 A024628 A061864 this_sequence A132288 A039380 A043203
Adjacent sequences: A075807 A075808 A075809 this_sequence A075811 A075812 A075813
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KEYWORD
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nonn,base
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AUTHOR
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Jani Melik (jani_melik(AT)hotmail.com), Oct 13 2002
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EXTENSIONS
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Edited by Dean Hickerson (dean(AT)math.ucdavis.edu), Oct 21 2002
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