A243067 -id:A243067 - cp's OEIS frontend

A163510 Irregular table read by rows: Write n in binary. For each 1, the m-th term of row n is the number of 0's between the m-th 1, reading right to left, and the (m-1)th 1 (or the right side of the number if m-1 = 0).

0, 1, 0, 0, 2, 0, 1, 1, 0, 0, 0, 0, 3, 0, 2, 1, 1, 0, 0, 1, 2, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 4, 0, 3, 1, 2, 0, 0, 2, 2, 1, 0, 1, 1, 1, 0, 1, 0, 0, 0, 1, 3, 0, 0, 2, 0, 1, 1, 0, 0, 0, 1, 0, 2, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 5, 0, 4, 1, 3, 0, 0, 3, 2, 2, 0, 1, 2, 1, 0, 2, 0, 0, 0, 2, 3, 1, 0, 2, 1, 1, 1, 1, 0, 0, 1, 1, 2, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1

Offset: 1

Leroy Quet, Jul 29 2009

Row n contains exactly A000120(n) terms, for each n.
All odd-numbered rows begin with 0. All even-numbered rows begin with a positive integer.
Can be used to compute the permutation A163511.

			Table begins as:
  Row  n in    Terms on
   n   binary  that row
   1      1    0; (the distance of 1-bit from the right edge is zero)
   2     10    1; (the distance of 1-bit from the right edge is one)
   3     11    0,0;
   4    100    2;
   5    101    0,1; (the least significant 1-bit is zero steps away from the right edge, and there is one zero between those two 1-bits)
   6    110    1,0;
   7    111    0,0,0;
   8   1000    3;
   9   1001    0,2;
  10   1010    1,1;
  11   1011    0,0,1;
  12   1100    2,0;
  13   1101    0,1,0;
  14   1110    1,0,0;
  15   1111    0,0,0,0;
  16  10000    4;

Antti Karttunen, Table of n, a(n) for n = 1..11265

Cf. A000120, A006068, A100922, A227186, A243067, A163511, A227736.

Equals A228351-1, termwise.

Table[Reverse@ Map[Ceiling[(Length@ # - 1)/2] &, DeleteCases[Split@ Join[Riffle[IntegerDigits[n, 2], 0], {0}], {k__} /; k == 1]], {n, 46}] // Flatten (* Michael De Vlieger, Jul 25 2016 *)

from itertools import count, islice
def A163510_gen(): # generator of terms
    for n in count(1):
        k = n
        while k:
            yield (s:=(~k&k-1).bit_length())
            k >>= s+1
A163510_list = list(islice(A163510_gen(),30)) # Chai Wah Wu, Jul 17 2023

(define (A163510 n) (- (A227186bi (A006068 (A100922 (- n 1))) (A243067 n)) 1))
;; See A227186 for A227186bi. - Antti Karttunen, Jun 19 2014

a(n) = A227186(A006068(A100922(n-1)), A243067(n)) - 1. - Antti Karttunen, Jun 19 2014

Additional terms computed and Example section added by Antti Karttunen, Jun 19 2014

A100922 k appears A000120(k) times (appearances equal number of 1-bits).

Original entry on oeis.org

1, 2, 3, 3, 4, 5, 5, 6, 6, 7, 7, 7, 8, 9, 9, 10, 10, 11, 11, 11, 12, 12, 13, 13, 13, 14, 14, 14, 15, 15, 15, 15, 16, 17, 17, 18, 18, 19, 19, 19, 20, 20, 21, 21, 21, 22, 22, 22, 23, 23, 23, 23, 24, 24, 25, 25, 25, 26, 26, 26, 27, 27, 27, 27, 28, 28, 28, 29, 29, 29, 29, 30, 30, 30, 30

Offset: 0

Rick L. Shepherd, Nov 21 2004

Clearly every positive integer appears at least once in this sequence.

			The binary representation of 16 is 10000, which has one 1-bit (and four 0-bits), hence 16 appears once in this sequence (and four times in A100921).

Antti Karttunen, Table of n, a(n) for n = 0..11264

Cf. A100921 (n's appearances equal its number of 0-bits), A030530 (n's appearances equal its total number of bits), A227737 (n's appearances equal its total number of runs), A000069, A000120, A000788, A163510, A243067.

T:= n-> n$add(i, i=Bits[Split](n)):
seq(T(n), n=1..30);  # Alois P. Heinz, Nov 11 2024

Table[Table[n,DigitCount[n,2,1]],{n,30}]//Flatten (* Harvey P. Dale, Aug 31 2017 *)

def A000788(n): return (n+1)*n.bit_count()+(sum((m:=1<>j)-(r if n<<1>=m*(r:=k<<1|1) else 0)) for j in range(1,n.bit_length()+1))>>1)
def A100922(n):
    if n == 0: return 1
    m, k = 1, 1
    while A000788(m)<=n: m<<=1
    while m-k>1:
        r = m+k>>1
        if A000788(r)>n:
            m = r
        else:
            k = r
    return m # Chai Wah Wu, Nov 11 2024

a(n) = the least k such that A000788(k) > n. - Antti Karttunen, Jun 20 2014

Sum_{n>=1} (-1)^(n+1)/a(n) = Sum_{n>=1} (-1)^(n+1)/A000069(n) = 0.67968268... . - Amiram Eldar, Feb 18 2024

cp's OEIS Frontend

A163510 Irregular table read by rows: Write n in binary. For each 1, the m-th term of row n is the number of 0's between the m-th 1, reading right to left, and the (m-1)th 1 (or the right side of the number if m-1 = 0).

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