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A110725
[{n concatenate R(n)} + {R(n) concatenate n}]/11, where R(n) = digit reversal of n.
4
0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 101, 202, 303, 404, 505, 606, 707, 808, 909, 1010, 202, 303, 404, 505, 606, 707, 808, 909, 1010, 1111, 303, 404, 505, 606, 707, 808, 909, 1010, 1111, 1212, 404, 505, 606, 707, 808, 909, 1010, 1111, 1212, 1313, 505
OFFSET
0,2
LINKS
FORMULA
A110724(n)/11.
When n has one digit, a(n)=2*n. When n has two digits, a(n)= 101*x + 101*y. (Here x,y are the digits of n.). - _Keith Schneider_, Jun 16 2007
EXAMPLE
a(12) = {1221 + 2112}/11 = 303. a(68) = {6886 + 8668}/11 = 1414.
MATHEMATICA
Table[(FromDigits[Join[IntegerDigits[n], Reverse[IntegerDigits[n]]]] + FromDigits[Join[Reverse[IntegerDigits[n]], IntegerDigits[n]]])/11, {n, 0, 50}] (* Stefan Steinerberger, Jun 17 2007 *)
cr[n_]:=Module[{r=IntegerReverse[n]}, (n*10^IntegerLength[n]+r+ r*10^ IntegerLength[ n]+n)/11]; Array[cr, 60, 0] (* Harvey P. Dale, Nov 10 2017 *)
CROSSREFS
KEYWORD
base,nonn,less,easy
AUTHOR
Amarnath Murthy, Aug 09 2005
EXTENSIONS
Corrected and extended by Stefan Steinerberger, Jun 17 2007
STATUS
approved