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A075806
Differences between adjacent palindromic numbers which are products of an odd number of distinct primes.
0
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
OFFSET
1,2
EXAMPLE
a(1)=3-2=1, a(2)=5-3=2, a(5)=66-11=55.
MAPLE
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)];
CROSSREFS
Cf. A037010.
Sequence in context: A257618 A088895 A257619 * A295580 A177956 A345758
KEYWORD
nonn,base
AUTHOR
Jani Melik, Oct 13 2002
EXTENSIONS
Edited by Dean Hickerson, Oct 21 2002
STATUS
approved