|
|
A165071
|
|
a(n) = image of n under the base-7 Kaprekar map n -> (n with digits sorted into descending order) - (n with digits sorted into ascending order)
|
|
30
|
|
|
0, 0, 0, 0, 0, 0, 0, 6, 0, 6, 12, 18, 24, 30, 12, 6, 0, 6, 12, 18, 24, 18, 12, 6, 0, 6, 12, 18, 24, 18, 12, 6, 0, 6, 12, 30, 24, 18, 12, 6, 0, 6, 36, 30, 24, 18, 12, 6, 0, 48, 48, 96, 144, 192, 240, 288, 48, 0, 48, 96, 144, 192, 240, 96, 48, 48, 96, 144, 192, 240, 144, 96, 96, 96
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,8
|
|
LINKS
|
|
|
EXAMPLE
|
For n = 11, 11_10 = 14_7. So, a(11) = 41_7 - 14_7 = 29 - 11 = 18. - Indranil Ghosh, Feb 02 2017
|
|
MATHEMATICA
|
a[n_] := With[{dd = IntegerDigits[n, 7]}, FromDigits[ReverseSort[dd], 7] - FromDigits[Sort[dd], 7]];
|
|
CROSSREFS
|
|
|
KEYWORD
|
base,nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|