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A075817
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Palindromic even numbers with an odd number of prime factors (counted with multiplicity).
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0
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2, 8, 44, 66, 212, 222, 242, 252, 272, 282, 292, 404, 434, 464, 474, 494, 606, 616, 646, 656, 696, 828, 848, 888, 2222, 2552, 2882, 4004, 4224, 4334, 4554, 4664, 4884, 4994, 6006, 6226, 6336, 6446, 6886, 6996, 8118, 8228, 8338, 8558, 8778, 8888, 8998
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refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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LINKS
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Table of n, a(n) for n=1..47.
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EXAMPLE
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8=2^3, 222=2*3*37 and 4004=2^2*7*11*13 are palindromic, even and products of an odd 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 type(numtheory[bigomega](n), odd); end; a := []; for n from 2 to 21000 by 2 do if test(n) then a := [op(a), n]; end; od; a;
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CROSSREFS
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Cf. A046470.
Sequence in context: A324670 A334335 A283416 * A264565 A018985 A018986
Adjacent sequences: A075814 A075815 A075816 * A075818 A075819 A075820
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KEYWORD
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nonn,base
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AUTHOR
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Jani Melik, Oct 13 2002
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EXTENSIONS
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Edited by Dean Hickerson, Oct 22 2002
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STATUS
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approved
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