A272020 -id:A272020 - cp's OEIS frontend

A372427 Numbers whose binary indices and prime indices have the same sum.

19, 33, 34, 69, 74, 82, 130, 133, 305, 412, 428, 436, 533, 721, 755, 808, 917, 978, 1036, 1058, 1062, 1121, 1133, 1143, 1341, 1356, 1630, 1639, 1784, 1807, 1837, 1990, 2057, 2115, 2130, 2133, 2163, 2260, 2324, 2328, 2354, 2358, 2512, 2534, 2627, 2771, 2825

Offset: 1

Gus Wiseman, May 01 2024

A binary index of n is any position of a 1 in its reversed binary expansion. The binary indices of n are row n of A048793.

A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.

			The binary indices of 130 are {2,8}, and the prime indices are {1,3,6}. Both sum to 10, so 130 is in the sequence.
The terms together with their prime indices begin:
   19: {8}
   33: {2,5}
   34: {1,7}
   69: {2,9}
   74: {1,12}
   82: {1,13}
  130: {1,3,6}
  133: {4,8}
  305: {3,18}
  412: {1,1,27}
  428: {1,1,28}
The terms together with their binary expansions and binary indices begin:
   19:      10011 ~ {1,2,5}
   33:     100001 ~ {1,6}
   34:     100010 ~ {2,6}
   69:    1000101 ~ {1,3,7}
   74:    1001010 ~ {2,4,7}
   82:    1010010 ~ {2,5,7}
  130:   10000010 ~ {2,8}
  133:   10000101 ~ {1,3,8}
  305:  100110001 ~ {1,5,6,9}
  412:  110011100 ~ {3,4,5,8,9}
  428:  110101100 ~ {3,4,6,8,9}

John Tyler Rascoe, Table of n, a(n) for n = 1..10000

For length instead of sum we get A071814.
Positions of zeros in A372428.
For maximum instead of sum we have A372436.
A003963 gives product of prime indices.
A019565 gives Heinz number of binary indices, adjoint A048675.
A029837 gives greatest binary index, least A001511.
A048793 lists binary indices, length A000120, reverse A272020, sum A029931.
A061395 gives greatest prime index, least A055396.
A070939 gives length of binary expansion.
A096111 gives product of binary indices.
A112798 lists prime indices, length A001222, reverse A296150, sum A056239.
A326031 gives weight of the set-system with BII-number n.
Cf. A000720, A001221, A014499, A030101, A066099, A304818, A318283, A355536, A359401, A359402, A372429-A372433, A372441.

prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
bix[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
Select[Range[100],Total[prix[#]]==Total[bix[#]]&]

A372436 Numbers whose binary indices and prime indices have the same maximum.

Original entry on oeis.org

3, 5, 14, 22, 39, 52, 68, 85, 102, 119, 133, 152, 171, 190, 209, 228, 247, 276, 299, 322, 345, 368, 391, 414, 437, 460, 483, 506, 522, 551, 580, 609, 638, 667, 696, 725, 754, 783, 812, 841, 870, 928, 957, 986, 1015, 1054, 1085, 1116, 1178, 1209, 1240, 1302

Offset: 1

Gus Wiseman, May 04 2024

A binary index of n is any position of a 1 in its reversed binary expansion. The binary indices of n are row n of A048793.
A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
Note that a number's binary and prime indices cannot have the same minimum; see A372437.

			The binary indices of 345 are {1,4,5,7,9}, and the prime indices are {2,3,9}. Both have maximum 9, so 345 is in the sequence.
The terms together with their prime indices begin:
     3: {2}
     5: {3}
    14: {1,4}
    22: {1,5}
    39: {2,6}
    52: {1,1,6}
    68: {1,1,7}
    85: {3,7}
   102: {1,2,7}
   119: {4,7}
   133: {4,8}
   152: {1,1,1,8}
   171: {2,2,8}
The terms together with their binary expansions and binary indices begin:
     3:           11 ~ {1,2}
     5:          101 ~ {1,3}
    14:         1110 ~ {2,3,4}
    22:        10110 ~ {2,3,5}
    39:       100111 ~ {1,2,3,6}
    52:       110100 ~ {3,5,6}
    68:      1000100 ~ {3,7}
    85:      1010101 ~ {1,3,5,7}
   102:      1100110 ~ {2,3,6,7}
   119:      1110111 ~ {1,2,3,5,6,7}
   133:     10000101 ~ {1,3,8}
   152:     10011000 ~ {4,5,8}
   171:     10101011 ~ {1,2,4,6,8}

For length instead of maximum we have A071814.
For sum instead of maximum we have A372427.
Positions of zeros in A372442, for minimum instead of maximum A372437.
A003963 gives product of prime indices.
A019565 gives Heinz number of binary indices, adjoint A048675.
A029837 gives greatest binary index, least A001511.
A048793 lists binary indices, length A000120, reverse A272020, sum A029931.
A061395 gives greatest prime index, least A055396.
A070939 gives length of binary expansion.
A112798 lists prime indices, length A001222, reverse A296150, sum A056239.
Cf. A000720, A014499, A030101, A066099, A096111, A304818, A355536, A359401, A359402, A372428-A372433, A372441.

bix[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[100],Max[prix[#]]==Max[bix[#]]&]

A070939(a(n)) = A061395(a(n)).

A209281 Start with first run [0,1] then, for n >= 2, the n-th run has length 2^n and is the concatenation of [a(1),a(2),...,a(2^n/2)] and [n-a(1),n-a(2),...,n-a(2^n/2)].

Original entry on oeis.org

0, 1, 2, 1, 3, 2, 1, 2, 4, 3, 2, 3, 1, 2, 3, 2, 5, 4, 3, 4, 2, 3, 4, 3, 1, 2, 3, 2, 4, 3, 2, 3, 6, 5, 4, 5, 3, 4, 5, 4, 2, 3, 4, 3, 5, 4, 3, 4, 1, 2, 3, 2, 4, 3, 2, 3, 5, 4, 3, 4, 2, 3, 4, 3, 7, 6, 5, 6, 4, 5, 6, 5, 3, 4, 5, 4, 6, 5, 4, 5, 2, 3, 4, 3, 5, 4, 3

Offset: 1

Benoit Cloitre, Jan 16 2013

Also the sum of the odd bisection (odd-indexed parts) of the (n-1)-th composition in standard order, where the k-th composition in standard order (graded reverse-lexicographic, A066099) is obtained by taking the set of positions of 1's in the reversed binary expansion of k, prepending 0, taking first differences, and reversing again. Note that this sequence counts {} as composition number 1 (instead of the usual 0). For example, composition number 741 in standard order is (2,1,1,3,2,1), with odd bisection (2,1,2), so a(742) = 2 + 1 + 2 = 5. - Gus Wiseman, Aug 24 2021

			[0,1] -> [0,1] U [2-0,2-1] =
[0,1,2,1] -> [0,1,2,1] U [3-0,3-1,3-2,3-1] =
[0,1,2,1,3,2,1,2] etc.
From _Gus Wiseman_, Aug 08 2021: (Start)
As a triangle without the initial 0, row-lengths A000079:
  1
  2 1
  3 2 1 2
  4 3 2 3 1 2 3 2
  5 4 3 4 2 3 4 3 1 2 3 2 4 3 2 3
  6 5 4 5 3 4 5 4 2 3 4 3 5 4 3 4 1 2 3 2 4 3 2 3 5 4 3 4 2 3 4 3
(End)

Cf. A010060 (Thue-Morse), A103204 (indices of 1's).
Cf. A029837 (binary order), A000120 (binary weight), A006068 (inverse Gray), A272020 (bit positions).
Cf. A089215.
As a triangle: A000079 (row lengths), A001792 (row sums).
Other composition part sums: A124754. A346633.
Also the sum of row A346702(n-1) of A066099.
Cf. A346697 (on prime indices).

Table[Total[First/@Partition[Append[Differences[Prepend[Join@@Position[Reverse[IntegerDigits[n,2]],1],0]]//Reverse,0],2]],{n,0,100}] (* Gus Wiseman, Aug 08 2021 *)

/* compute 2^15 terms */ v=[0,1];for(n=2,15,v=concat(v,vector(2^n/2,i,n-v[i]));a(n)=v[n];)

a(n) = n--; my(s=1,ns); while((ns=n>>s), n=bitxor(n,ns); s<<=1); hammingweight(n); \\ Kevin Ryde, May 14 2022

Let T(n)=A010060(n) then for n>=1 a(2n)=a(n)+1-T(n-1) and a(2n+1)=a(n+1)+T(n).
For n>=2 a(n) = a(ceiling(n/2))+T(n-1) hence:
a(n) = Sum_{k=0..ceiling(log(n-1)/log(2))} T(floor((n-1)/2^k)).
For k>=0 a(3*2^k+1)=1 (more precisely a(n)=1 iff n is in A103204), a(2^k+1)=k+1, a(5*2^k+1)=2, a(7*2^k+1)=k+2 etc.
From Gus Wiseman, Aug 18 2021: (Start)
a(n + 1) = (A029837(n) + A124754(n))/2.
a(n + 1) = A029837(n) - A346633(n).
a(n + 1) = A346633(n) - A124754(n).
a(n + 1) = A029837(A346702(n)).
(End)
From Kevin Ryde, May 14 2022: (Start)
a(n) = A000120(A006068(n-1)), binary weight of inverse binary Gray code.
a(n) = Sum_{k=1..A000120(n-1)} (-1)^(k-1) * A272020(n-1,k), alternating sum of 1-bit positions.
a(n) = A089215(n) - 1.
(End)

A372428 Sum of binary indices of n minus sum of prime indices of n.

Original entry on oeis.org

1, 1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 3, 2, 4, 5, 1, -1, 2, 0, 3, 3, 4, 2, 4, 4, 4, 6, 6, 3, 8, 4, 1, 0, 0, 2, 3, -2, 2, 4, 4, -2, 5, -1, 6, 7, 5, 1, 5, 4, 6, 5, 6, -1, 9, 9, 8, 6, 6, 1, 11, 1, 8, 13, 1, -1, 1, -9, 1, 0, 4, -7, 4, -9, 0, 6, 4, 6, 7, -5, 5, 5, 0, -8

Offset: 1

Gus Wiseman, May 02 2024

A binary index of n is any position of a 1 in its reversed binary expansion. The binary indices of n are row n of A048793.

A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.

			The binary indices of 65 are {1,7}, and the prime indices are {3,6}, so a(65) = 8 - 9 = -1.

John Tyler Rascoe, Table of n, a(n) for n = 1..10000

Positions of zeros are A372427.
For minimum instead of sum we have A372437.
For length instead of sum we have A372441, zeros A071814.
For maximum instead of sum we have A372442, zeros A372436.
Positions of odd terms are A372586, even A372587.
A003963 gives product of prime indices.
A019565 gives Heinz number of binary indices, adjoint A048675.
A029837 gives greatest binary index, least A001511.
A048793 lists binary indices, length A000120, reverse A272020, sum A029931.
A061395 gives greatest prime index, least A055396.
A070939 gives length of binary expansion.
A096111 gives product of binary indices.
A112798 lists prime indices, length A001222, reverse A296150, sum A056239.
A326031 gives weight of the set-system with BII-number n.
Cf. A000720, A001221, A014499, A030101, A059893, A066099, A243055, A304818, A359495, A372429-A372432.

prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
bix[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
Table[Total[bix[n]]-Total[prix[n]],{n,100}]

from itertools import count, islice
from sympy import sieve, factorint
def a_gen():
    for n in count(1):
        b = sum((i+1) for i, x in enumerate(bin(n)[2:][::-1]) if x =='1')
        p = sum(sieve.search(i)[0] for i in factorint(n, multiple=True))
        yield(b-p)
A372428_list = list(islice(a_gen(), 83)) # John Tyler Rascoe, May 04 2024

from sympy import primepi, factorint
def A372428(n): return int(sum(i for i, j in enumerate(bin(n)[:1:-1],1) if j=='1')-sum(primepi(p)*e for p, e in factorint(n).items())) # Chai Wah Wu, Oct 18 2024

a(n) = A029931(n) - A056239(n).

A372471 Irregular triangle read by rows where row n lists the binary indices of the n-th prime number.

Original entry on oeis.org

2, 1, 2, 1, 3, 1, 2, 3, 1, 2, 4, 1, 3, 4, 1, 5, 1, 2, 5, 1, 2, 3, 5, 1, 3, 4, 5, 1, 2, 3, 4, 5, 1, 3, 6, 1, 4, 6, 1, 2, 4, 6, 1, 2, 3, 4, 6, 1, 3, 5, 6, 1, 2, 4, 5, 6, 1, 3, 4, 5, 6, 1, 2, 7, 1, 2, 3, 7, 1, 4, 7, 1, 2, 3, 4, 7, 1, 2, 5, 7, 1, 4, 5, 7, 1, 6, 7

Offset: 1

Gus Wiseman, May 07 2024

A binary index of n is any position of a 1 in its reversed binary expansion. The binary indices of n are row n of A048793.

			We have prime(12) = (2^1 + 2^3 + 2^6)/2, so row 12 is (1,3,6).
Each prime followed by its binary indices:
   2: 2
   3: 1 2
   5: 1 3
   7: 1 2 3
  11: 1 2 4
  13: 1 3 4
  17: 1 5
  19: 1 2 5
  23: 1 2 3 5
  29: 1 3 4 5
  31: 1 2 3 4 5
  37: 1 3 6
  41: 1 4 6
  43: 1 2 4 6
  47: 1 2 3 4 6

Row lengths are A014499.
Second column is A023506(n) + 1.
Final column is A035100.
Prime-indexed rows of A048793.
Row-sums are A372429, restriction of A029931 (sum of binary indices).
A019565 gives Heinz number of binary indices, adjoint A048675.
A029837 gives greatest binary index, least A001511.
A048793 lists binary indices, length A000120, reverse A272020.
A070939 gives length of binary expansion.
Cf. A000040, A005940, A056239, A071814, A096111, A191232, A230877, A231204, A372427-A372442.

Table[Join@@Position[Reverse[IntegerDigits[Prime[n],2]],1],{n,15}]

A372442 (Greatest binary index of n) minus (greatest prime index of n).

Original entry on oeis.org

1, 0, 2, 0, 1, -1, 3, 2, 1, -1, 2, -2, 0, 1, 4, -2, 3, -3, 2, 1, 0, -4, 3, 2, -1, 3, 1, -5, 2, -6, 5, 1, -1, 2, 4, -6, -2, 0, 3, -7, 2, -8, 1, 3, -3, -9, 4, 2, 3, -1, 0, -10, 4, 1, 2, -2, -4, -11, 3, -12, -5, 2, 6, 1, 2, -12, 0, -2, 3, -13, 5, -14, -5, 4, -1

Offset: 2

Gus Wiseman, May 07 2024

A binary index of n is any position of a 1 in its reversed binary expansion. The binary indices of n are row n of A048793.

A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.

For sum instead of maximum we have A372428, zeros A372427.
Positions of zeros are A372436.
For minimum instead of maximum we have A372437, zeros {}.
For length instead of maximum we have A372441, zeros A071814.
Positions of odd terms are A372588, even A372589.
A019565 gives Heinz number of binary indices, adjoint A048675.
A029837 gives greatest binary index, least A001511.
A048793 lists binary indices, length A000120, reverse A272020, sum A029931.
A061395 gives greatest prime index, least A055396.
A070939 gives length of binary expansion.
A112798 lists prime indices, length A001222, reverse A296150, sum A056239.
Cf. A000720, A003963, A014499, A174090, A243055, A355536, A359495, A372429-A372432, A372589-A372591.

bix[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Table[Max[bix[n]]-Max[prix[n]],{n,2,100}]

a(n) = A070939(n) - A061395(n) = A029837(n) - A061395(n) for n > 1.

A272011 Irregular triangle read by rows: strictly decreasing sequences of nonnegative numbers given in lexicographic order.

Original entry on oeis.org

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

Offset: 0

Peter Kagey, Apr 17 2016

Length of n-th row given by A000120(n);
Maximum of n-th row given by A000523(n);
Minimum of n-th row given by A007814(n);
GCD of n-th row given by A064894(n);
Sum of n-th row given by A073642(n + 1).
n-th row begins at index A000788(n - 1) for n > 0.
The first appearance of n is at A001787(n).
a(A001787(n) + 1) = a(A001787(n)) for all n > 0.
a(A001787(n) + 2) = 0 for all n > 0.
a(A001787(n) + 3) = a(A001787(n)) for all n > 1.
a(A001787(n) + 4) = 1 for all n > 1.
a(A001787(n) + 5) = a(A001787(n)) for all n > 1.
Row n < 1024 lists the digits of A262557(n). - M. F. Hasler, Dec 11 2019

			Row n is given by the exponents in the binary expansion of n. For example, row 5 = [2, 0] because 5 = 2^2 + 2^0.
Row 0: []
Row 1: [0]
Row 2: [1]
Row 3: [1, 0]
Row 4: [2]
Row 5: [2, 0]
Row 6: [2, 1]
Row 7: [2, 1, 0]

Peter Kagey, Table of n, a(n) for n = 0..10000

Cf. A000120, A000523, A001787, A007814, A064894, A073642.
Cf. A133457 gives the rows in reverse order.
Cf. A272020, A262557.

Map[Length[#] - Flatten[Position[#, 1]] &, IntegerDigits[Range[50], 2]] (* Paolo Xausa, Feb 13 2024 *)

apply( A272011_row(n)=Vecrev(vecextract([0..exponent(n+!n)],n)), [0..39]) \\ For n < 2^10: row(n)=digits(A262557[n]). There are 2^k rows starting with k, they start at row 2^k. - M. F. Hasler, Dec 11 2019

A277905 Irregular table: Each row n (n >= 0) lists in ascending order all A018819(n) numbers k for which A048675(k) = n.

Original entry on oeis.org

1, 2, 3, 4, 6, 8, 5, 9, 12, 16, 10, 18, 24, 32, 15, 20, 27, 36, 48, 64, 30, 40, 54, 72, 96, 128, 7, 25, 45, 60, 80, 81, 108, 144, 192, 256, 14, 50, 90, 120, 160, 162, 216, 288, 384, 512, 21, 28, 75, 100, 135, 180, 240, 243, 320, 324, 432, 576, 768, 1024, 42, 56, 150, 200, 270, 360, 480, 486, 640, 648, 864, 1152, 1536, 2048, 35, 63, 84, 112, 125, 225, 300, 400

Offset: 1

Antti Karttunen, Nov 14 2016

Each row beginning with an odd number (rows with even index) is followed by a row of the same length, with the same terms, but multiplied by 2. See also comments in the Formula section of A018819.
Note that although the indexing of rows start from zero, the indexing of this sequence starts from 1, with a(1) = 1.
Also Heinz numbers of integer partitions whose binary rank is n, where the binary rank of a partition y is given by Sum_i 2^(y_i-1). For example, row n = 6 is 15, 20, 27, 36, 48, 64, corresponding to the partitions (3,2), (3,1,1), (2,2,2), (2,2,1,1), (2,1,1,1,1), (1,1,1,1,1,1). - Gus Wiseman, May 25 2024
Also, row n lists in ascending order all A018819(n) numbers k for which A097248(k) = A019565(n). - Flávio V. Fernandes, Jul 19 2025

			The irregular table begins as:
  row terms
   0   1;
   1   2;
   2   3,  4;
   3   6,  8;
   4   5,  9,  12,  16;
   5  10, 18,  24,  32;
   6  15, 20,  27,  36,  48,  64;
   7  30, 40,  54,  72,  96, 128;
   8   7, 25,  45,  60,  80,  81, 108, 144, 192, 256;
   9  14, 50,  90, 120, 160, 162, 216, 288, 384, 512;
  10  21, 28,  75, 100, 135, 180, 240, 243, 320, 324, 432,  576,  768, 1024;
  11  42, 56, 150, 200, 270, 360, 480, 486, 640, 648, 864, 1152, 1536, 2048;
...

Antti Karttunen, Table of n, a(n) for n = 1..166
Index entries for sequences that are permutations of the natural numbers

Cf. A019565 (the left edge, the only terms that are squarefree).
Cf. A000079 (the trailing edge).
Cf. A048675, A260443, A277886, A277896, A277903, A277904.
Row lengths are A018819 (number of partitions of binary rank n).
A000009 counts strict partitions, ranks A005117.
A029837 stc_sum or A070939 bin_len, opposite A070940 binexp_lastpos_1.
A048675 gives binary rank of prime indices, distinct A087207.
A048793 lists binary indices, product A096111, reverse A272020.
A061395 gives greatest prime index, least A055396.
A112798 lists prime indices, cf. A001222, A003963, A056239, A296150.
A372890 adds up binary ranks of partitions, strict A372888.
Cf. A000040, A000041, A001511, A005940, A118462, A215366, A225620, A246868.
Cf. A097248, A048675.

prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n], {p_,k_}:>Table[PrimePi[p],{k}]]]];
Table[Select[Range[0,2^k],Total[2^(prix[#]-1)]==k&],{k,0,10}] (* Gus Wiseman, May 25 2024 *)

(definec (A277905 n) (A277905bi (A277903 n) (A277904 n)))
(define (A277905bi row col) (let outloop ((k (A019565 row)) (col col)) (if (zero? col) k (let inloop ((j (+ 1 k))) (if (= (A048675 j) row) (outloop j (- col 1)) (inloop (+ 1 j))))))) ;; Very slow implementation.
;; Implementation based on a naive recurrence:
(definec (A277905 n) (if (= 1 n) n (let ((maybe_next (A277896 (A277905 (- n 1))))) (if (not (zero? maybe_next)) maybe_next (A019565 (A277903 n))))))

a(1) = 1; for n > 1, if A277896(a(n-1)) > 0, then a(n) = A277896(a(n-1)), otherwise a(n) = A019565(A277903(n)). [A naive recurrence for a one-dimensional version.]
Other identities. For all n >= 1:
A048675(a(n)) = A277903(n).

A333769 Irregular triangle read by rows where row k is the sequence of run-lengths of the k-th composition in standard order.

Original entry on oeis.org

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

Offset: 0

Gus Wiseman, Apr 10 2020

A composition of n is a finite sequence of positive integers summing to n. The k-th composition in standard order (graded reverse-lexicographic, A066099) is obtained by taking the set of positions of 1's in the reversed binary expansion of k, prepending 0, taking first differences, and reversing again. This gives a bijective correspondence between nonnegative integers and integer compositions.

			The standard compositions and their run-lengths:
   0:        () -> ()
   1:       (1) -> (1)
   2:       (2) -> (1)
   3:     (1,1) -> (2)
   4:       (3) -> (1)
   5:     (2,1) -> (1,1)
   6:     (1,2) -> (1,1)
   7:   (1,1,1) -> (3)
   8:       (4) -> (1)
   9:     (3,1) -> (1,1)
  10:     (2,2) -> (2)
  11:   (2,1,1) -> (1,2)
  12:     (1,3) -> (1,1)
  13:   (1,2,1) -> (1,1,1)
  14:   (1,1,2) -> (2,1)
  15: (1,1,1,1) -> (4)
  16:       (5) -> (1)
  17:     (4,1) -> (1,1)
  18:     (3,2) -> (1,1)
  19:   (3,1,1) -> (1,2)
For example, the 119th composition is (1,1,2,1,1,1), so row 119 is (2,1,3).

Row sums are A000120.
Row lengths are A124767.
Row k is the A333627(k)-th standard composition.
A triangle counting compositions by runs-resistance is A329744.
All of the following pertain to compositions in standard order (A066099):
- Partial sums from the right are A048793.
- Sum is A070939.
- Adjacent equal pairs are counted by A124762.
- Strict compositions are A233564.
- Partial sums from the left are A272020.
- Constant compositions are A272919.
- Normal compositions are A333217.
- Heinz number is A333219.
- Runs-resistance is A333628.
- First appearances of run-resistances are A333629.
- Combinatory separations are A334030.
Cf. A029931, A098504, A114994, A181819, A182850, A225620, A228351, A238279, A242882, A318928, A329747, A333489, A333630.

stc[n_]:=Differences[Prepend[Join@@Position[Reverse[IntegerDigits[n,2]],1],0]]//Reverse;
Table[Length/@Split[stc[n]],{n,0,30}]

A360189 Triangle T(n,k), n>=0, 0<=k<=floor(log_2(n+1)), read by rows: T(n,k) = number of nonnegative integers <= n having binary weight k.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 2, 1, 1, 3, 1, 1, 3, 2, 1, 3, 3, 1, 3, 3, 1, 1, 4, 3, 1, 1, 4, 4, 1, 1, 4, 5, 1, 1, 4, 5, 2, 1, 4, 6, 2, 1, 4, 6, 3, 1, 4, 6, 4, 1, 4, 6, 4, 1, 1, 5, 6, 4, 1, 1, 5, 7, 4, 1, 1, 5, 8, 4, 1, 1, 5, 8, 5, 1, 1, 5, 9, 5, 1, 1, 5, 9, 6, 1, 1, 5, 9, 7, 1

Offset: 0

Alois P. Heinz, Mar 04 2023

T(n,k) is defined for all n >= 0 and k >= 0. Terms that are not in the triangle are zero.

			T(6,2) = 3: 3, 5, 6, or in binary: 11_2, 101_2, 110_2.
T(15,3) = 4: 7, 11, 13, 14, or in binary: 111_2, 1011_2, 1101_2, 1110_2.
Triangle T(n,k) begins:
  1;
  1, 1;
  1, 2;
  1, 2, 1;
  1, 3, 1;
  1, 3, 2;
  1, 3, 3;
  1, 3, 3, 1;
  1, 4, 3, 1;
  1, 4, 4, 1;
  1, 4, 5, 1;
  1, 4, 5, 2;
  1, 4, 6, 2;
  1, 4, 6, 3;
  1, 4, 6, 4;
  1, 4, 6, 4, 1;
  ...

Alois P. Heinz, Rows n = 0..2^12-1, flattened
Peter J. Taylor, Closed form for Sum_{k=0..n} [wt(k) = m] where wt(n) is the binary weight of n, answer to question on MathOverflow (2024).
Wikipedia, Iverson bracket

Columns k=0-2 give: A000012, A029837(n+1) = A113473(n) for n>0, A340068(n+1).
Last elements of rows give A090996(n+1).
Cf. A000027, A000120, A000225, A000788, A006046, A007318, A116520, A116522, A116525, A116526, A130665, A130667, A161342, A231500, A231501, A231502, A272020, A361257.

b:= proc(n) option remember; `if`(n<0, 0,
      b(n-1)+x^add(i, i=Bits[Split](n)))
    end:
T:= n-> (p-> seq(coeff(p, x, i), i=0..degree(p)))(b(n)):
seq(T(n), n=0..23);

T(n,k) = my(v1); v1 = Vecrev(binary(n+1)); v1 = Vecrev(select(x->(x>0),v1,1)); sum(j=0, min(k,#v1-1), binomial(v1[j+1]-1,k-j)) \\ Mikhail Kurkov, Nov 27 2024

T(n,k) = T(n-1,k) + [A000120(n) = k] where [] is the Iverson bracket and T(n,k) = 0 for n<0.
T(2^n-1,k) = A007318(n,k) = binomial(n,k).
T(n,floor(log_2(n+1))) = A090996(n+1).
Sum_{k>=0} T(n,k) = n+1.
Sum_{k>=0} k * T(n,k) = A000788(n).
Sum_{k>=0} k^2 * T(n,k) = A231500(n).
Sum_{k>=0} k^3 * T(n,k) = A231501(n).
Sum_{k>=0} k^4 * T(n,k) = A231502(n).
Sum_{k>=0} 2^k * T(n,k) = A006046(n+1).
Sum_{k>=0} 3^k * T(n,k) = A130665(n).
Sum_{k>=0} 4^k * T(n,k) = A116520(n+1).
Sum_{k>=0} 5^k * T(n,k) = A130667(n+1).
Sum_{k>=0} 6^k * T(n,k) = A116522(n+1).
Sum_{k>=0} 7^k * T(n,k) = A161342(n+1).
Sum_{k>=0} 8^k * T(n,k) = A116526(n+1).
Sum_{k>=0} 10^k * T(n,k) = A116525(n+1).
Sum_{k>=0} n^k * T(n,k) = A361257(n).
T(n,k) = Sum_{j=0..min(k, A000120(n+1)-1)} binomial(A272020(n+1,j+1)-1,k-j) for n >= 0, k >= 0 (see Peter J. Taylor link). - Mikhail Kurkov, Nov 27 2024

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