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 A263307 Numbers without consecutive repeated digits in base 2 and in base 3. 0
 1, 2, 5, 10, 21, 1365, 2730 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Intersection of A000975 and A031941. - Michel Marcus, Oct 14 2015 It seems likely that there are no further terms. LINKS EXAMPLE 10 is 1010 in base 2 and 101 in base 3; no two of the same digit are next to one another and so 10 is a term. Similarly 21 is 10101 in base 2 and 210 in base 3 so it is also a term. PROG (PARI) isokd(d) = {dd = vector(#d-1, k, abs(d[k+1]-d[k])); if (#dd, vecmin(dd), 1); } isok(n) = isokd(binary(n)) && isokd(digits(n, 3)); \\ Michel Marcus, Oct 14 2015 CROSSREFS Cf. A000975 (base 2), A031941 (base 3). Sequence in context: A327764 A192317 A151497 * A278441 A323939 A110744 Adjacent sequences:  A263304 A263305 A263306 * A263308 A263309 A263310 KEYWORD nonn,base AUTHOR Robin Powell, Oct 13 2015 STATUS approved

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Last modified May 18 00:59 EDT 2022. Contains 353779 sequences. (Running on oeis4.)