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A222815
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Numbers (not ending in 0) which are 4 times their digit-reversal.
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6
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8712, 87912, 879912, 8799912, 87128712, 87999912, 871208712, 879999912, 8712008712, 8791287912, 8799999912, 87120008712, 87912087912, 87999999912, 871200008712, 871287128712, 879120087912, 879912879912, 879999999912, 8712000008712, 8712879128712, 8791200087912
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OFFSET
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1,1
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COMMENTS
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There are Fibonacci(floor((n-2)/2)) terms with n digits (this is essentially A103609). - Ray Chandler, Oct 12 2017
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LINKS
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MATHEMATICA
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okQ[t_]:=t==Reverse[t]&&First[t]!=0&&Min[Length/@Split[t]]>1; Sort[Flatten[ (4*198)#&/@Flatten[Table[FromDigits/@Select[Tuples[{0, 1}, n], okQ], {n, 12}]]]] (* Harvey P. Dale, Jul 03 2013 *)
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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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STATUS
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approved
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