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A089633 Numbers having no more than one 0 in their binary representation. 35
0, 1, 2, 3, 5, 6, 7, 11, 13, 14, 15, 23, 27, 29, 30, 31, 47, 55, 59, 61, 62, 63, 95, 111, 119, 123, 125, 126, 127, 191, 223, 239, 247, 251, 253, 254, 255, 383, 447, 479, 495, 503, 507, 509, 510, 511, 767, 895, 959, 991, 1007, 1015, 1019, 1021, 1022, 1023 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
A023416(a(n)) <= 1; A023416(a(n)) = A023532(n-2) for n>1;
A000120(a(u)) <= A000120(a(v)) for u<v; A000120(a(n)) = A003056(n).
Complement of A158582. - Reinhard Zumkeller, Apr 16 2009
Also union of A168604 and A030130. - Douglas Latimer, Jul 19 2012
Numbers of the form 2^t - 2^k - 1, 0 <= k < t.
A029931(a(n)) = n and A029931(m) != n for m < a(n). - Reinhard Zumkeller, Feb 28 2014
A265705(a(n),k) = A265705(a(n),a(n)-k), k = 0 .. a(n). - Reinhard Zumkeller, Dec 15 2015
n is in the sequence if and only if 2*n+1 is in the sequence. - Robert Israel, Dec 14 2018
LINKS
Vladimir Shevelev, On the Basis Polynomials in the Theory of Permutations with Prescribed Up-Down Structure, arXiv:0801.0072 [math.CO], 2007-201. See Section 14.
Vladimir Shevelev, Binomial Coefficient Predictors, Journal of Integer Sequences, Vol. 14 (2011), Article 11.2.8.
FORMULA
a(0)=0, n>0: a(n+1) = Min{m>n: BinOnes(a(n))<=BinOnes(m)} with BinOnes=A000120.
If m = floor((sqrt(8*n+1) - 1) / 2), then a(n) = 2^(m+1) - 2^(m*(m+3)/2 - n) - 1. - Carl R. White, Feb 10 2009
a(A014132(n)-1) = 2*a(n-1)+1 for n >= 1. - Robert Israel, Dec 14 2018
EXAMPLE
From Tilman Piesk, May 09 2012: (Start)
This may also be viewed as a triangle: In binary:
0 0
1 2 01 10
3 5 6 011 101 110
7 11 13 14 0111 1011 1101 1110
15 23 27 29 30 01111 10111 11011 11101 11110
31 47 55 59 61 62
63 95 111 119 123 125 126
Left three diagonals are A000225, A055010, A086224. Right diagonal is A000918. Central column is A129868. Numbers in row n (counted from 0) have n binary 1s. (End)
MAPLE
seq(seq(2^a-1-2^b, b=a-1..0, -1), a=1..11); # Robert Israel, Dec 14 2018
MATHEMATICA
fQ[n_] := DigitCount[n, 2, 0] < 2; Select[ Range[0, 2^10], fQ] (* Robert G. Wilson v, Aug 02 2012 *)
PROG
(Haskell)
a089633 n = a089633_list !! (n-1)
a089633_list = [2 ^ t - 2 ^ k - 1 | t <- [1..], k <- [t-1, t-2..0]]
-- Reinhard Zumkeller, Feb 23 2012
(PARI) {insq(n) = local(dd, hf, v); v=binary(n); hf=length(v); dd=sum(i=1, hf, v[i]); if(dd<=hf-2, -1, 1)}
{for(w=0, 1536, if(insq(w)>=0, print1(w, ", ")))}
\\ Douglas Latimer, May 07 2013
(PARI) isoka(n) = #select(x->(x==0), binary(n)) <= 1; \\ Michel Marcus, Dec 14 2018
(Python)
from itertools import count, islice
def A089633_gen(): # generator of terms
return ((1<<t)-(1<<k)-1 for t in count(1) for k in range(t-1, -1, -1))
A089633_list = list(islice(A089633_gen(), 30)) # Chai Wah Wu, Feb 10 2023
CROSSREFS
Cf. A181741 (primes), union of A081118 and A000918, apart from initial -1.
Cf. A265705.
Sequence in context: A342392 A053328 A333786 * A362815 A358772 A003172
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Jan 01 2004
STATUS
approved

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Last modified December 11 00:22 EST 2023. Contains 367717 sequences. (Running on oeis4.)