A187786 Table read by rows, where n-th row contains all numbers having in binary representation as many zeros and ones as n.

0, 1, 2, 3, 4, 5, 6, 5, 6, 7, 8, 9, 10, 12, 9, 10, 12, 11, 13, 14, 9, 10, 12, 11, 13, 14, 11, 13, 14, 15, 16, 17, 18, 20, 24, 17, 18, 20, 24, 19, 21, 22, 25, 26, 28, 17, 18, 20, 24, 19, 21, 22, 25, 26, 28, 19, 21, 22, 25, 26, 28, 23, 27, 29, 30, 17, 18, 20

Offset

0,3

Comments

For k = 0..A090706(n)-1: A023416(T(n,k))=A023416(n); A000120(T(n,k))=A000120(n); A053644(n)<=T(n,k)<=A003817(n);

T(n,k) = n for some k;

A187769 contains all rows without repetitions.

Links

Reinhard Zumkeller, Rows n = 0..255 of triangle, flattened

Index entries for sequences related to binary expansion of n

Example

.  n  n-th row              binary                          row length
. --  --------------------- ------------------------------- ----------
.  0  {0}                   {0}                                      1
.  1  {1}                   {1}                                      1
.  2  {2}                   {10}                                     1
.  3  {3}                   {11}                                     1
.  4  {4}                   {100}                                    1
.  5  {5,6}                 {101,110}                                2
.  6  {5,6}                 {101,110}                                2
.  7  {7}                   {111}                                    1
.  8  {8}                   {1000}                                   1
.  9  {9,10,12}             {1001,1010,1100}                         3
. 10  {9,10,12}             {1001,1010,1100}                         3
. 11  {11,13,14}            {1011,1101,1110}                         3
. 12  {9,10,12}             {1001,1010,1100}                         3
. 13  {11,13,14}            {1011,1101,1110}                         3
. 14  {11,13,14}            {1011,1101,1110}                         3
. 15  {15}                  {1111}                                   1
. 16  {16}                  {10000}                                  1
. 17  {17,18,20,24}         {10001,10010,10100,11000}                4
. 18  {17,18,20,24}         {10001,10010,10100,11000}                4
. 19  {19,21,22,25,26,28}   {10011,10101,10110,11001,11010,11100}    6
. 20  {17,18,20,24}         {10001,10010,10100,11000}                4 .

Prog

(Haskell)
import List (find)
import Maybe (fromJust)
a187786 n k = a187786_tabf !! n !! k
a187786_row n = fromJust $ find (elem n) a187769_tabf
a187786_tabf = map a187786_row [0..]

Crossrefs

Sequence in context: A309279 A245352 A099033 * A002330 A374211 A335130

Adjacent sequences: A187783 A187784 A187785 * A187787 A187788 A187789

Keyword

nonn,base,tabf,look

Author

Reinhard Zumkeller, Jan 06 2013

Status

approved