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 A290869 Numbers that are repdigits with length > 2 in more than two bases. 10
 4095, 32767, 65535, 67053, 262143, 265720, 531440, 1048575, 2097151, 4381419, 5592405, 7174453, 9808617, 11184810, 13938267, 14348906, 16777215, 19617234, 21523360, 29425851, 39234468, 43046720, 48686547, 49043085, 58851702, 61035156, 68660319, 71270178 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Most of the terms of A167783 are repdigits with length > 2 in only two bases. For any b > 1 and k > 2, b^(4*k)-1 is a repdigit with length > 2 in bases b, b^2 and b^4; hence this sequence is infinite. - Rémy Sigrist, Aug 19 2017 LINKS Rémy Sigrist, Table of n, a(n) for n = 1..777 Rémy Sigrist, C# program for A290869 Rémy Sigrist, C++ program for A290869 EXAMPLE 67053 is a repdigit with more than 2 digits in three bases: [31,31,31]_46, [21,21,21]_56, [3,3,3]_149. PROG (PARI) isok(n)=my(nb = 0); for (b=2, n-1, d = digits(n, b); if ((#d > 2) && (#Set(d) == 1), nb++); if (nb > 2, return (1)); ); return (0); (C#) See Links section. (C++) See Links section. CROSSREFS Subsequence of A167783. Sequence in context: A359084 A043452 A261593 * A075952 A075957 A075953 Adjacent sequences: A290866 A290867 A290868 * A290870 A290871 A290872 KEYWORD nonn,base AUTHOR Michel Marcus, Aug 13 2017 EXTENSIONS More terms from Giovanni Resta, Aug 13 2017 STATUS approved

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Last modified October 4 03:55 EDT 2023. Contains 365872 sequences. (Running on oeis4.)