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 A258165 Odd non-Brazilian numbers > 1. 2
 3, 5, 9, 11, 17, 19, 23, 25, 29, 37, 41, 47, 49, 53, 59, 61, 67, 71, 79, 83, 89, 97, 101, 103, 107, 109, 113, 131, 137, 139, 149, 151, 163, 167, 169, 173, 179, 181, 191, 193, 197, 199, 223, 227, 229, 233, 239, 251, 257, 263, 269, 271, 277, 281, 283, 289, 293, 311, 313, 317, 331, 337 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Complement of A257521 in A144396 (odd numbers > 1). The terms are only odd primes or squares of odd primes. Most odd primes are present except those in A085104. All terms which are not primes are squares of odd primes except 121 = 11^2. LINKS Vincenzo Librandi, Table of n, a(n) for n = 1..1150 EXAMPLE 11 is present because there is no base b < 11 - 1 = 10 such that the representation of 11 in base b is a repdigit (all digits are equal). In fact, we have: 11 = 1011_2 = 102_3 = 23_4 = 21_5 = 15_6 = 14_7 = 13_8 = 12_9, and none of these representations are repdigits. - Bernard Schott, Jun 21 2017 MATHEMATICA fQ[n_] := Block[{b = 2}, While[b < n - 1 && Length@ Union@ IntegerDigits[n, b] > 1, b++]; b+1 == n]; Select[1 + 2 Range@ 170, fQ] PROG (PARI) forstep(n=3, 300, 2, c=1; for(b=2, n-2, d=digits(n, b); if(vecmin(d)==vecmax(d), c=0;  break)); if(c, print1(n, ", "))) \\ Derek Orr, May 27 2015 (Python) from sympy.ntheory.factor_ import digits l=[] for n in range(3, 301, 2):     c=1     for b in range(2, n - 1):         d=digits(n, b)[1:]         if max(d)==min(d):             c=0             break     if c: l.append(n) print(l) # Indranil Ghosh, Jun 22 2017, after PARI program CROSSREFS Cf. A085104, A125134, A190300, A220570, A220571, A220627, A242397, A253260, A253261, A257521. Sequence in context: A111039 A114512 A118113 * A076193 A056533 A329110 Adjacent sequences:  A258162 A258163 A258164 * A258166 A258167 A258168 KEYWORD nonn AUTHOR Daniel Lignon and Robert G. Wilson v, May 22 2015 STATUS approved

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Last modified August 10 03:38 EDT 2022. Contains 356029 sequences. (Running on oeis4.)