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%I #19 Jan 03 2021 00:44:58
%S 142857,5436,36,2826,1,9,279,252,2439,214857,552,3348,27,37,207,3573,
%T 3,3384,27,3564,2439,25371,37,2538,34857,2085,2115,31968,21207,2772,
%U 2295,2516,24975,237681,2718,212535,21663,21645,2439,227934,2199,219465,2049768,20478,2178,2002185,208596,2043792,2031939
%N a(n) is the smallest number such that a(n)*n is an anagram of a(n)*5.
%C a(n) does not exist for n >= 50 because a(n)*n >= 10*(a(n)*5) has more digits than a(n)*5. - _Robert Israel_, Nov 03 2014
%e a(6)=9 because 6*9 = 54, 5*9 = 45 and 54 is an anagram of 45.
%p f:= proc(n)
%p local d, k, a5;
%p for d from 0 to 10 do
%p for k from ceil(10^d/5) to floor(10^(d+1)/n) do
%p a5:= sort(convert(k*5,base,10));
%p if sort(convert(k*n,base,10)) = a5 then return k fi
%p od
%p od
%p end proc:
%p seq(f(n),n=1..49); # _Robert Israel_, Nov 03 2014
%t f[n_] := Block[ {k = 1}, While[ Sort@ IntegerDigits[5 k] != Sort@ IntegerDigits[k*n], k++ ]; k]; Array[f, 45] (* _Robert G. Wilson v_, Aug 15 2010 *)
%K base,nonn,fini,full
%O 1,1
%A _Claudio Meller_, Aug 09 2010
%E More terms from _Robert G. Wilson v_, Aug 15 2010
%E a(43) to a(49) from _Robert Israel_, Nov 03 2014
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