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A222815 Numbers (not ending in 0) which are 4 times their digit-reversal. 6
8712, 87912, 879912, 8799912, 87128712, 87999912, 871208712, 879999912, 8712008712, 8791287912, 8799999912, 87120008712, 87912087912, 87999999912, 871200008712, 871287128712, 879120087912, 879912879912, 879999999912, 8712000008712, 8712879128712, 8791200087912 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There are Fibonacci(floor((n-2)/2)) terms with n digits (this is essentially A103609). - Ray Chandler, Oct 12 2017

LINKS

Ray Chandler, Table of n, a(n) for n = 1..10000

N. J. A. Sloane, 2178 And All That, Fib. Quart., 52 (2014), 99-120.

MATHEMATICA

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 *)

CROSSREFS

Equals 4*A008918.

Sequence in context: A170796 A035909 A031877 * A233679 A266578 A031852

Adjacent sequences:  A222812 A222813 A222814 * A222816 A222817 A222818

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Mar 11 2013

STATUS

approved

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Last modified November 28 23:48 EST 2021. Contains 349415 sequences. (Running on oeis4.)