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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
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, 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, 1, 1, 5, 2, 2, 3, 3, 3, 3, 1, 5, 2, 2, 4, 4, 1, 2, 2, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

COMMENTS

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.

LINKS

Michel Lagneau, Table of n, a(n) for n = 1..5000

EXAMPLE

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.

MAPLE

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:

CROSSREFS

Cf. A066460, A125134.

Sequence in context: A316384 A029838 A213649 * A023132 A023124 A023120

Adjacent sequences:  A242394 A242395 A242396 * A242398 A242399 A242400

KEYWORD

nonn,base

AUTHOR

Michel Lagneau, May 13 2014

STATUS

approved

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Last modified April 19 21:57 EDT 2021. Contains 343117 sequences. (Running on oeis4.)