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 A242397 a(n) is the number of different bases b such that the Brazilian numbers A125134(n) remain a repdigit number. 2

%I

%S 1,1,1,1,1,1,2,1,2,1,2,1,3,2,1,2,2,2,2,1,1,1,3,1,1,4,3,1,2,2,1,4,2,1,

%T 2,3,1,2,2,1,5,2,4,2,1,3,2,1,3,4,1,1,2,2,1,3,5,1,1,5,2,2,1,3,4,2,2,2,

%U 1,1,5,2,2,3,3,3,3,1,5,2,2,4,4,1,2,2,1

%N a(n) is the number of different bases b such that the Brazilian numbers A125134(n) remain a repdigit number.

%C For all numbers m, we restrict the bases b with 1 < b < m-1 because m is repdigit in bases 1 and also m-1.

%H Michel Lagneau, <a href="/A242397/b242397.txt">Table of n, a(n) for n = 1..5000</a>

%e a(89) = 7 because A125134(89)=120 and the number 120 is AA in base 11 where A = 10, 88 in base 14, 66 in base 19, 55 in base 23, 44 in base 29, 33 in base 39 and 22 in base 59 => 7 representations.

%p for n from 1 to 200 do:c:=0:for b from 2 to n-2 do:x:=convert(n,base,b):n1:=nops(x):a:=x[n1]:i:=1:for k from n1-1 by -1 to 1 do:if x[k]=a then i:=i+1:else fi:od:if i=n1 then c:=c+1:i:=1:else fi:od:if c>0 then printf(`%d, `,c):else fi:od:

%Y Cf. A066460, A125134.

%K nonn,base

%O 1,7

%A _Michel Lagneau_, May 13 2014

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Last modified May 6 17:59 EDT 2021. Contains 343586 sequences. (Running on oeis4.)