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 A004781 Binary expansion contains 3 adjacent 1's. 6
 7, 14, 15, 23, 28, 29, 30, 31, 39, 46, 47, 55, 56, 57, 58, 59, 60, 61, 62, 63, 71, 78, 79, 87, 92, 93, 94, 95, 103, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 135, 142, 143, 151, 156, 157, 158, 159, 167 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 Index entries for 2-automatic sequences. FORMULA a(n) ~ n. - Charles R Greathouse IV, Sep 24 2012 MAPLE q:= n-> verify([1\$3], Bits[Split](n), 'sublist'): select(q, [\$0..200])[]; # Alois P. Heinz, Oct 22 2021 MATHEMATICA Select[Range[200], MemberQ[Partition[IntegerDigits[#, 2], 3, 1], {1, 1, 1}]&] (* Harvey P. Dale, Mar 31 2011 *) Select[Range[200], StringContainsQ[IntegerString[#, 2], "111"] &] (* Amiram Eldar, Oct 22 2021 *) Select[Range[200], SequenceCount[IntegerDigits[#, 2], {1, 1, 1}]>0&] (* Harvey P. Dale, Dec 28 2021 *) PROG (Haskell) a004781 n = a004781_list !! (n - 1) a004781_list = filter f [0..] where f x | x < 7 = False | otherwise = (x `mod` 8) == 7 || f (x `div` 2) -- Reinhard Zumkeller, Jun 03 2012 (PARI) is(n)=!!bitand(bitand(n, n<<1), n<<2) \\ Charles R Greathouse IV, Sep 24 2012 CROSSREFS Complement of A003726. Cf. A004779, A136037. Sequence in context: A085335 A069137 A141164 * A004759 A364287 A062056 Adjacent sequences: A004778 A004779 A004780 * A004782 A004783 A004784 KEYWORD nonn,base,easy AUTHOR N. J. A. Sloane EXTENSIONS Offset corrected by Reinhard Zumkeller, Jun 03 2012 STATUS approved

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Last modified April 16 17:36 EDT 2024. Contains 371749 sequences. (Running on oeis4.)