login
A222814
Numbers (not ending in 0) which are 9 times their digit-reversal.
7
9801, 98901, 989901, 9899901, 98019801, 98999901, 980109801, 989999901, 9801009801, 9890198901, 9899999901, 98010009801, 98901098901, 98999999901, 980100009801, 980198019801, 989010098901, 989901989901, 989999999901, 9801000009801, 9801989019801, 9890100098901
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
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[ (9*99)#&/@Flatten[Table[FromDigits/@Select[Tuples[{0, 1}, n], okQ], {n, 12}]]]] (* Harvey P. Dale, Jul 03 2013 *)
CROSSREFS
Equals 9*A001232.
Sequence in context: A145209 A035911 A069333 * A156735 A227489 A350918
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Mar 11 2013
STATUS
approved