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 A153033 Numbers with adjacent 1's and no adjacent 0's in binary expansion. 2
 3, 6, 7, 11, 13, 14, 15, 22, 23, 26, 27, 29, 30, 31, 43, 45, 46, 47, 53, 54, 55, 58, 59, 61, 62, 63, 86, 87, 90, 91, 93, 94, 95, 106, 107, 109, 110, 111, 117, 118, 119, 122, 123, 125, 126, 127, 171, 173, 174, 175, 181, 182, 183, 186, 187, 189, 190, 191, 213, 214, 215 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE a(1)=3 because bin(3)= 11. MAPLE filter:= proc(n) local L; L:= convert(n, base, 2); L:= L[1..-2]+L[2..-1]; has(L, 2) and not has(L, 0) end proc: select(filter, [\$3..300]); # Robert Israel, Jun 17 2020 MATHEMATICA fQ[n_] := Block[{st = Union@ Split@ IntegerDigits[n, 2]}, MemberQ[st, {1, __}] && !MemberQ[st, {0, __}]]; Select[Range@218, fQ@# &] (* Robert G. Wilson v, Dec 21 2008 *) Select[Range[300], SequenceCount[IntegerDigits[#, 2], {0, 0}]== 0 && SequenceCount[ IntegerDigits[#, 2], {1, 1}]>0&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 11 2017 *) CROSSREFS Sequence in context: A306718 A022550 A237883 * A353240 A282167 A076644 Adjacent sequences: A153030 A153031 A153032 * A153034 A153035 A153036 KEYWORD base,easy,nonn AUTHOR Gil Broussard, Dec 17 2008 EXTENSIONS Extended by Robert G. Wilson v, Dec 21 2008 STATUS approved

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Last modified November 30 23:40 EST 2023. Contains 367464 sequences. (Running on oeis4.)