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a(n) = arrange digits of concatenation of divisors of n (A037278, A176558) in increasing order in base 10 (zero digits are omitted).
5

%I #5 Sep 08 2022 08:46:08

%S 1,12,13,124,15,1236,17,1248,139,1125,111,1122346,113,11247,11355,

%T 112468,117,1123689,119,112245,11237,111222,123,1122234468,1255,

%U 112236,12379,11224478,129,111233556,113,11223468,111333,112347,13557,111223346689,137

%N a(n) = arrange digits of concatenation of divisors of n (A037278, A176558) in increasing order in base 10 (zero digits are omitted).

%C See A243362 = sequence of numbers n such that a(n) = 123456789: 54023, 54203, 500407, 23456789… First prime in this sequence is 23456789.

%e For n = 20; divisors of 20: 1, 2, 4, 5, 10, 20; a(20) = 112245.

%o (Magma) A243361:=func<n | Seqint(Reverse(Sort(&cat[(Intseq(k)): k in Divisors(n)])))>; [A243361(n): n in [1..100]]

%Y Cf. A037278, A176558, A243360, A243362, A243363, A243364.

%K nonn,base

%O 1,2

%A _Jaroslav Krizek_, Jun 04 2014