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Numbers whose set of base 11 digits is {0,A}, where A base 11 = 10 base 10.
2

%I #27 May 28 2016 15:06:38

%S 0,10,110,120,1210,1220,1320,1330,13310,13320,13420,13430,14520,14530,

%T 14630,14640,146410,146420,146520,146530,147620,147630,147730,147740,

%U 159720,159730,159830,159840,160930,160940,161040,161050,1610510

%N Numbers whose set of base 11 digits is {0,A}, where A base 11 = 10 base 10.

%C n such that there exists a permutation p_1, ..., p_n of 1, ..., n such that i + p_i is a power of 11 for every i.

%H Vincenzo Librandi, <a href="/A097257/b097257.txt">Table of n, a(n) for n = 0..1000</a>

%F a(n) = 10*A033047(n).

%F a(2n) = 11*a(n), a(2n+1) = a(2n)+10.

%t f[n_] := FromDigits[ IntegerDigits[n, 2] /. {1 -> 10}, 11]; Array[f, 33, 0] (* or much slower *)

%t fQ[n_] := Union@ Join[{0, 10}, IntegerDigits[n, 11]] == {0, 10}; Select[ Range[0, 1610519], fQ] (* _Robert G. Wilson v_, May 12 2012 *)

%t Join[{0},Union[Flatten[Table[FromDigits[#,11]&/@(Join[{10},#]&/@ Tuples[ {10,0},n]),{n,0,5}]]]] (* _Harvey P. Dale_, Sep 23 2013 *)

%o (PARI) {for(vv=0,32,

%o bvv=binary(vv);

%o texp=0;btb=0;

%o forstep(i=length(bvv),1,-1,btb=btb+10*bvv[i]*11^texp;texp++);

%o print1(btb,", ") )} \\ _Douglas Latimer_, May 12 2012

%Y Cf. A001196, A005823, A097251-A097262.

%K nonn,base

%O 0,2

%A _Ray Chandler_, Aug 03 2004