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A023095
a(n) is the least k > 0 such that k and 3k are anagrams in base n (written in base 10).
1
75, 142, 315, 12, 819, 84, 1035, 15, 198, 2766, 9555, 56, 315, 8352, 20893, 45, 950, 22000, 819, 132, 63204, 24492, 114075, 91, 2646, 938, 30015, 240, 182807, 118592, 333795, 153, 5670, 187416, 73815, 380, 623610, 176820, 5699, 231, 10406, 489808
OFFSET
4,1
COMMENTS
2*a(n) is divisible by n-1. - Robert Israel, Mar 20 2017
MAPLE
for n from 4 to 100 do
searching:= true:
if n::even then delta:= n-1 else delta:= (n-1)/2 fi;
for d from 1 while searching do
for x from n^(d-1)+delta-1 to floor(n^d/3) by delta while searching do
if sort(convert(x, base, n)) = sort(convert(3*x, base, n)) then
searching:= false; A[n]:= x;
fi
od od od:
seq(A[i], i=4..100); # Robert Israel, Mar 20 2017
MATHEMATICA
Table[k = 1; While[! Equal @@ Map[Sort@ IntegerDigits[#, n] &, {k, 3 k}], k++]; k, {n, 4, 45}] (* Michael De Vlieger, Mar 20 2017 *)
CROSSREFS
Sequence in context: A118225 A260538 A361487 * A044326 A044707 A228306
KEYWORD
nonn,base
STATUS
approved