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 A291312 Numbers that contain exactly one pair of identical digits x and a triple of identical digits y (x not equal y). 0
 10001, 10010, 10011, 10100, 10101, 10110, 11000, 11001, 11010, 11100, 11122, 11133, 11144, 11155, 11166, 11177, 11188, 11199, 11212, 11221, 11222, 11313, 11331, 11333, 11414, 11441, 11444, 11515, 11551, 11555, 11616, 11661, 11666, 11717, 11771, 11777, 11818, 11881, 11888, 11919, 11991, 11999, 12112, 12121, 12122, 12211, 12212, 12221 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Since other digits may be present, the last term is 9998876543210; otherwise the last term would be 99988 (as communicated by Giovanni Resta). LINKS MATHEMATICA ok[n_] := Block[{d = DigitCount[n]}, Count[d, 2] == 1 == Count[d, 3] && {} == Select[d, # > 3 &]]; Select[Range[22200], ok] (* Giovanni Resta, Aug 25 2017 *) CROSSREFS Sequence in context: A091566 A113758 A273531 * A203591 A115850 A082567 Adjacent sequences:  A291309 A291310 A291311 * A291313 A291314 A291315 KEYWORD nonn,base,fini AUTHOR Enrique Navarrete, Aug 21 2017 STATUS approved

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Last modified November 30 22:59 EST 2021. Contains 349426 sequences. (Running on oeis4.)