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Seven-digit terms in A023086 Numbers n such that n and 2*n are anagrams.
2

%I #12 Feb 15 2017 04:13:30

%S 1025874,1028574,1042587,1042857,1052874,1054287,1072854,1074285,

%T 1078524,1078542,1085274,1085427,1087254,1087425,1087524,1087542,

%U 1207854,1208754,1240785,1240875,1245789,1245879,1247589,1247859

%N Seven-digit terms in A023086 Numbers n such that n and 2*n are anagrams.

%C All 288 terms have only two sets of digits: {{0,1,2,4,5,7,8},{1,2,4,5,7,8,9}} with exactly equal numbers of both sets = 144.

%C There are six 7-d numbers n such that n, 2*n and 4*n are anagrams, that is intersection of 7-d subsequences in A023086 and A023088: 1294857, 1428507, 1428570, 1428705, 1429857, 1492857.

%C These are all "norep" numbers, i.e., numbers with any repetitive digit are not permitted. [From Harvey P. Dale, Oct 30 2011]

%H Zak Seidov, <a href="/A159816/b159816.txt">Table of n, a(n) for n = 1..288</a>

%e a(1)=1025874 because 1025874 and 2*1025874=2051748 both use the same set of digits {0,1,2,4,5,7,8};

%e a(21)=1245789 because 1245789 and 2*1245789=2491578 both use the same set of digits {1,2,4,5,7,8,9}.

%t anaQ[n_]:=Max[DigitCount[n]]==1&&Union[IntegerDigits[n]] == Union[ IntegerDigits[2n]]; Select[Range[1000000,1250000],anaQ] (* _Harvey P. Dale_, Oct 30 2011 *)

%Y A023086 n and 2k are anagrams, A023088 n and 4n are anagrams.

%K base,nonn,fini,full

%O 1,1

%A _Zak Seidov_, Apr 22 2009