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%I #19 Jul 30 2017 12:53:12
%S 7,8,22,33,44,55,66,77,88,99,111,222,333,444,555,666,777,888,999,1111,
%T 2222,3333,4444,5555,6666,7777,8888,9999,11111,22222,33333,44444,
%U 55555,66666,77777,88888,99999,111111,222222,333333,444444,555555,666666,777777,888888,999999
%N Repdigits in base 10 which are Brazilian numbers.
%C These numbers are all repdigits belonging to A010785. The representation of the numbers 7 and 8 in base 10 is not Brazilian but they are yet Brazilian because 7 = 111_2 and 8 = 22_3. Except the repdigits 7, 8, 22, 33, 55, 77 and the primes repunits R_n from A004022 and A004023, all these Brazilian repdigits are also Brazilian in another base.
%e 7 = 111_2;
%e 44 = 44_10 = 22_21;
%e 66 = 66_10 = 33_21 = 22_32.
%t Select[Flatten@ Table[FromDigits@ ConstantArray[k, n], {n, 6}, {k, 9}], Function[n, Length@ SelectFirst[Range[2, n - 2], Count[DigitCount[n, #], _?(# > 0 &)] == 1 &] == 0]] (* _Michael De Vlieger_, Jun 06 2017, Version 10 *)
%Y Cf. A004022, A004023, A010785, A014181, A125134,
%K nonn,base
%O 1,1
%A _Bernard Schott_, Jun 05 2017
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