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A075806
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Differences between adjacent palindromic numbers which are products of an odd number of distinct primes.
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0
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1, 2, 2, 4, 55, 35, 30, 20, 30, 10, 31, 60, 31, 40, 20, 10, 51, 40, 20, 61, 40, 11, 40, 81, 30, 20, 10, 10, 122, 10, 40, 32, 220, 330, 220, 451, 660, 451, 220, 781, 660, 341, 220, 110, 220, 110, 11, 220, 220, 440, 451, 220, 110, 110, 110, 451, 220, 220, 220, 341
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OFFSET
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1,2
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LINKS
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EXAMPLE
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a(1)=3-2=1, a(2)=5-3=2, a(5)=66-11=55.
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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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