|
|
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
(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
|
|
|
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
|
|
|
KEYWORD
|
nonn,base
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|