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Search: a103589 -id:a103589
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"Sloping binary numbers": write numbers in binary under each other (right-justified), read diagonals in upward direction, convert to decimal.
+10
72
0, 3, 6, 5, 4, 15, 10, 9, 8, 11, 14, 13, 28, 23, 18, 17, 16, 19, 22, 21, 20, 31, 26, 25, 24, 27, 30, 61, 44, 39, 34, 33, 32, 35, 38, 37, 36, 47, 42, 41, 40, 43, 46, 45, 60, 55, 50, 49, 48, 51, 54, 53, 52, 63, 58, 57, 56, 59, 126, 93, 76, 71, 66, 65, 64, 67, 70, 69
OFFSET
0,2
COMMENTS
All terms are distinct, but certain terms (see A102371) are missing. But see A103122.
Trajectory of 1 is 1, 3, 5, 15, 17, 19, 21, 31, 33, ..., see A103192.
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..10000 (first 1001 terms from T. D. Noe)
David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers, J. Integer Seq. 8 (2005), no. 3, Article 05.3.6, 15 pp. Preprint versions: [pdf, ps].
FORMULA
a(n) = n + Sum_{ k >= 1 such that n + k == 0 mod 2^k } 2^k. (Cf. A103185.) In particular, a(n) >= n. - N. J. A. Sloane, Mar 18 2005
a(n) = A105027(A062289(n)) for n > 0. - Reinhard Zumkeller, Jul 21 2012
EXAMPLE
........0
........1
.......10
.......11
......100
......101
......110
......111
.....1000
.........
The upward-sloping diagonals are:
0
11
110
101
100
1111
1010
.......
giving 0, 3, 6, 5, 4, 15, 10, ...
The sequence has a natural decomposition into blocks (see the paper): 0; 3; 6, 5, 4; 15, 10, 9, 8, 11, 14, 13; 28, 23, 18, 17, 16, 19, 22, 21, 20, 31, 26, 25, 24, 27, 30; 61, ...
Reading the array of binary numbers along diagonals with slope 1 gives this sequence, slope 2 gives A105085, slope 0 gives A001477 and slope -1 gives A105033.
MAPLE
A102370:=proc(n) local t1, l; t1:=n; for l from 1 to n do if n+l mod 2^l = 0 then t1:=t1+2^l; fi; od: t1; end;
MATHEMATICA
f[n_] := Block[{k = 1, s = 0, l = Max[2, Floor[Log[2, n + 1] + 2]]}, While[k < l, If[ Mod[n + k, 2^k] == 0, s = s + 2^k]; k++ ]; s]; Table[ f[n] + n, {n, 0, 71}] (* Robert G. Wilson v, Mar 21 2005 *)
PROG
(PARI) A102370(n)=n-1+sum(k=0, ceil(log(n+1)/log(2)), if((n+k)%2^k, 0, 2^k)) \\ Benoit Cloitre, Mar 20 2005
(PARI) {a(n) = if( n<1, 0, sum( k=0, length( binary( n)), bitand( n + k, 2^k)))} /* Michael Somos, Mar 26 2012 */
(Haskell)
a102370 n = a102370_list !! n
a102370_list = 0 : map (a105027 . toInteger) a062289_list
-- Reinhard Zumkeller, Jul 21 2012
(Python)
def a(n): return 0 if n<1 else sum([(n + k)&(2**k) for k in range(len(bin(n)[2:]) + 1)]) # Indranil Ghosh, May 03 2017
CROSSREFS
Related sequences (1): A103542 (binary version), A102371 (complement), A103185, A103528, A103529, A103530, A103318, A034797, A103543, A103581, A103582, A103583.
Related sequences (2): A103584, A103585, A103586, A103587, A103127, A103192 (trajectory of 1), A103122, A103588, A103589, A103202 (sorted), A103205 (base 10 version).
Related sequences (3): A103747 (trajectory of 2), A103621, A103745, A103615, A103842, A103863, A104234, A104235, A103813, A105023, A105024, A105025, A105026, A105027, A105028.
Related sequences (4): A105029, A105030, A105031, A105032, A105033, A105034, A105035, A105108.
KEYWORD
nonn,nice,easy,base,look
AUTHOR
Philippe Deléham, Feb 13 2005
EXTENSIONS
More terms from Benoit Cloitre, Mar 20 2005
STATUS
approved
Binary array below read by downward antidiagonals.
+10
8
1, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
OFFSET
0,1
COMMENTS
The k-th row has alternating blocks of 2^k 1's followed by 2^k 0's:
1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, ...
1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, ...
1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, ...
1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, ...
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, ...
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, ...
...
LINKS
David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers [pdf, ps].
David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers, J. Integer Seq. 8 (2005), no. 3, Article 05.3.6, 15 pp.
MATHEMATICA
t = Table[ Take[ Flatten[ Table[ Join[ Table[1, {i, n}], Table[0, {i, n}]], {10}]], 15], {n, 15}]; Flatten[ Table[ t[[i, n - i + 1]], {n, 14}, {i, n}]] (* Robert G. Wilson v, Mar 24 2005 *)
CROSSREFS
KEYWORD
nonn,easy,tabl
AUTHOR
Philippe Deléham, Mar 24 2005
EXTENSIONS
More terms from Robert G. Wilson v and Benoit Cloitre, Mar 24 2005
Rechecked by David Applegate, Apr 19 2005
STATUS
approved
a(n) = n-th column sum of binary digits of k*2^(k-1), where summation is over k>=1, without carrying between columns.
+10
6
1, 0, 2, 1, 1, 1, 3, 2, 2, 0, 3, 2, 2, 2, 4, 3, 3, 1, 2, 2, 2, 2, 4, 3, 3, 1, 4, 3, 3, 3, 5, 4, 4, 2, 3, 1, 2, 2, 4, 3, 3, 1, 4, 3, 3, 3, 5, 4, 4, 2, 3, 3, 3, 3, 5, 4, 4, 2, 5, 4, 4, 4, 6, 5, 5, 3, 4, 2, 1, 2, 4, 3, 3, 1, 4, 3, 3, 3, 5, 4, 4, 2, 3, 3, 3, 3, 5, 4, 4, 2, 5, 4, 4, 4, 6, 5, 5, 3, 4, 2, 3, 3, 5, 4, 4
OFFSET
1,3
COMMENTS
sum(k=1,n, a(k)*2^(k-1)) = 2^A089399(n)+1 for n>2, with a(1)=a(2)=1.
Row sums of triangular arrays in A103588 and in A103589. - Philippe Deléham, Apr 04 2005
a(k) = 0 for k = 2, 10, 2058, 2058 + 2^2059, ..., that is, for k = A034797(n) - 1, n>=2. - Philippe Deléham, Nov 16 2007
FORMULA
a(2^n)=n-1 (for n>0), a(2^n-1)=n (for n>0), a(2^n+1)=n-1 (for n>1), a(2^n-k)=n-A089400(k) (for n>k>0), a(2^n+k)=n-A089401(k) (for n>k>0), where sequences have limits: A089400={0, 2, 2, 2, 1, 4, 2, 2, 1, 3, 3, ...} and A089401={1, 1, 3, 2, 4, 5, 6, 5, 7, 8, 11, 9, ...},
EXAMPLE
Binary expansions of k*2^(k-1), with bits in ascending order by powers of 2, are:
1
001
0011
000001
0000101
00000011
000000111
00000000001
000000001001
0000000000101
00000000001101
000000000000011
0000000000001011
.................
Giving column sums:
10211132203222433...
MATHEMATICA
f[n_] := Block[{lg = Floor[Log[2, n]] + 1}, Sum[ Join[ Reverse[ IntegerDigits[n - i + 1, 2]], {0}][[i]], {i, lg}]]; Table[ f[n], {n, 105}] (* Robert G. Wilson v, Mar 26 2005 *)
PROG
(PARI) /* Prints initial 1000 terms: */
{A=vector(1000); for(n=1, #A, Bn=binary(n*2^(n-1)); for(k=1, min(#Bn, #A), A[k]=A[k]+Bn[#Bn-k+1]) ); print(A)}
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Paul D. Hanna, Oct 30 2003
STATUS
approved
Same as A103582, but read antidiagonals in upward direction.
+10
6
1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1
OFFSET
0,1
COMMENTS
Successive digits of A103581.
LINKS
David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers [pdf, ps].
David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers, J. Integer Seq. 8 (2005), no. 3, Article 05.3.6, 15 pp.
MATHEMATICA
t = Table[ Take[ Flatten[ Table[ Join[ Table[1, {i, n}], Table[0, {i, n}]], {10}]], 15], {n, 15}]; Flatten[ Table[ t[[n - i + 1, i]], {n, 14}, {i, n}]] (* Robert G. Wilson v, Mar 24 2005 *)
CROSSREFS
KEYWORD
nonn,easy,tabl
AUTHOR
Philippe Deléham, Mar 24 2005
EXTENSIONS
Rechecked by David Applegate, Apr 19 2005
STATUS
approved
Read binary numbers downwards to the right.
+10
6
0, 1, 0, 3, 2, 1, 4, 7, 6, 5, 0, 11, 10, 9, 12, 15, 14, 13, 8, 3, 18, 17, 20, 23, 22, 21, 16, 27, 26, 25, 28, 31, 30, 29, 24, 19, 2, 33, 36, 39, 38, 37, 32, 43, 42, 41, 44, 47, 46, 45, 40, 35, 50, 49, 52, 55, 54, 53, 48, 59, 58, 57, 60, 63, 62, 61, 56, 51, 34, 1, 68, 71, 70, 69, 64, 75
OFFSET
0,4
COMMENTS
Equals A103530(n+2) - 1. - Philippe Deléham, Apr 06 2005
LINKS
David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers, J. Integer Seq. 8 (2005), no. 3, Article 05.3.6, 15 pp.
FORMULA
a(n) = n - Sum_{ k >= 0, 2^{k+1} <= n, n == k mod 2^(k+1) } 2^(k+1).
Structure: blocks of size 2^k taken from A105025, interspersed with terms a(n) itself! Thus a(2^k + k - 1 ) = a(k-1) for k >= 1.
From David Applegate, Apr 06 2005: (Start)
"a(n) = 2^k + a(n-2^k) if k >= 1 and 0 <= n - 2^k - k < 2^k, = a(n-2^k) if k >= 1 and n - 2^k - k = -1, or = 0 if n = 0 (and exactly one of the three conditions is true for any n >= 0).
"Equivalently, a(2^k + k + x) = 2^k + a(k+x) if 0 <= x < 2^k, = a(k+x) if x = -1 (for each n >= 0, there is a unique k, x such that 2^k + k + x = n, k >= 0, -1 <= x < 2^k). This recurrence follows immediately from the definition.
"The recurrence captures three observed facts about a: a(2^k + k - 1) = a(k-1); a consists of blocks of length 2^k of A105025 interspersed with terms of a; a(n) = n - Sum_{ k >= 0, 2^{k+1} <= n, n = k mod 2^(k+1) } 2^(k+1)." (End)
a(n) = sum_{k=0..n} A103589(n,k)*2^(n-k). - L. Edson Jeffery, Dec 01 2013
EXAMPLE
Start with the binary numbers:
........0
........1
.......10
.......11
......100
......101
......110
......111
.....1000
.........
and read downwards to the right, getting 0, 1, 0, 11, 10, 1, 100, 111, ...
MAPLE
f:= proc (n) local t1, l; t1 := n; for l from 0 to n do if `mod`(n-l, 2^(l+1)) = 0 and n >= 2^(l+1) then t1 := t1-2^(l+1) fi; od; t1; end proc;
MATHEMATICA
f[n_] := Block[{k = 0, s = 0}, While[2^(k + 1) < n + 1, If[ Mod[n, 2^(k + 1)] == k, s = s + 2^(k + 1)]; k++ ]; n - s]; Table[ f[n], {n, 0, 75}] (* Robert G. Wilson v, Apr 06 2005 *)
CROSSREFS
Analog of A102370. Cf. A105034, A105025.
Cf. triangular array in A103589.
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Apr 04 2005
STATUS
approved
1's complement of A103582.
+10
5
0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
OFFSET
0,1
COMMENTS
Comment from Jared Benjamin Ricks (jaredricks(AT)yahoo.com), Jan 31 2009: (Start)
This sequence be also be obtained in the following way. Write numbers in binary from left to right and read the resulting array by antidiagonals upwards:
0 : (0, 0, 0, 0, 0, 0, 0, ...)
1 : (1, 0, 0, 0, 0, 0, 0, ...)
2 : (0, 1, 0, 0, 0, 0, 0, ...)
3 : (1, 1, 0, 0, 0, 0, 0, ...)
4 : (0, 0, 1, 0, 0, 0, 0, ...)
5 : (1, 0, 1, 0, 0, 0, 0, ...)
6 : (0, 1, 1, 0, 0, 0, 0, ...)
7 : (1, 1, 1, 0, 0, 0, 0, ...)
... (End)
LINKS
David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers [pdf, ps].
EXAMPLE
Triangle begins:
0
1 0
0 0 0
1 1 0 0
0 1 0 0 0
1 0 0 0 0 0
0 0 1 0 0 0 0
1 1 1 0 0 0 0 0
0 1 1 0 0 0 0 0 0
1 0 1 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0
1 1 0 1 0 0 0 0 0 0 0 0
CROSSREFS
Cf. A103582, A103581, A103589. Considered as a triangle, obtained by reversing the rows of the triangle in A103589.
KEYWORD
nonn,easy,tabl
AUTHOR
Philippe Deléham, Mar 24 2005
EXTENSIONS
More terms from Robert G. Wilson v and Benoit Cloitre, Mar 26 2005
Corrected by N. J. A. Sloane, Apr 19, 2005
Rechecked by David Applegate, Apr 19 2005.
STATUS
approved
Binary equivalents of A105033.
+10
2
0, 1, 0, 11, 10, 1, 100, 111, 110, 101, 0, 1011, 1010, 1001, 1100, 1111, 1110, 1101, 1000, 11, 10010, 10001, 10100, 10111, 10110, 10101, 10000, 11011, 11010, 11001, 11100, 11111, 11110, 11101, 11000, 10011, 10, 100001, 100100, 100111, 100110
OFFSET
0,4
COMMENTS
Number of 1's in a(n) is A089398(n). - Philippe Deléham, Apr 05 2005.
The version 0, 01, 000, 0011, 00010, 000001, ... is obtained by interchanging 0 and 1 in A103581: 1, 10, 111, 1100, 11101, 111110, .... - Philippe Deléham, Apr 07 2005
LINKS
David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers [pdf, ps].
David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers, J. Integer Seq. 8 (2005), no. 3, Article 05.3.6, 15 pp.
CROSSREFS
Cf. triangular array in A103589.
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Apr 04 2005
EXTENSIONS
More terms from Benoit Cloitre, Apr 04 2005
STATUS
approved

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