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A075805
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Differences between adjacent palindromic numbers which are products of an even number of distinct primes.
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0
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5, 16, 11, 22, 22, 34, 30, 20, 41, 60, 41, 20, 70, 61, 51, 10, 20, 10, 20, 61, 81, 10, 20, 30, 51, 20, 20, 20, 20, 41, 10, 10, 20, 10, 122, 330, 220, 330, 11, 440, 561, 110, 110, 220, 440, 891, 231, 110, 1551, 451, 330, 550, 1122, 110, 220, 552, 100, 300, 400, 100
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history;
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internal format)
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(1)=6-1=5, a(2)=22-6=16.
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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; s := []; for n from 1 to 11000 do if test(n) then s := [op(s), n]; end; od; a := [op(2..-1, s)-op(1..-2, s)];
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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