cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-3 of 3 results.

A333398 Partial sums of A333400.

Original entry on oeis.org

0, -1, -3, -2, -5, -9, -7, -4, 1, 5, 11, 6, 13, 7, 15, 8, 17, 9, 19, 10, 21, 33, 23, 12, 25, 39, 27, 14, 29, 45, 31, 16, 34, 18, 35, 54, 37, 57, 38, 20, 41, 63, 43, 22, 46, 24, 47, 72, 49, 75, 51, 26, 53, 81, 55, 28, 58, 30, 59, 90, 61, 93, 62, 32, 65, 99, 67
Offset: 1

Views

Author

Alec Jones, Mar 18 2020

Keywords

Comments

Conjecture: This is a permutation of the integers.

Crossrefs

Cf. A333400.

A333401 a(n) is the distance between n and -n in A333400.

Original entry on oeis.org

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

Views

Author

Alec Jones, Mar 18 2020

Keywords

Comments

Records occur at n = 1, 2, 12, 18, 108, 216, 8856, ...
Interestingly, a(224) = a(225) = ... = a(441) = 3.

A367262 Lexicographically earliest sequence of distinct nonnegative integers such that the values a(0) XOR ... XOR a(k) (for some k >= 0) are all distinct (where XOR denotes the bitwise XOR operator).

Original entry on oeis.org

0, 1, 2, 4, 3, 6, 7, 8, 5, 14, 9, 16, 10, 11, 12, 15, 13, 25, 17, 18, 19, 21, 22, 20, 24, 29, 23, 32, 26, 27, 28, 30, 31, 49, 33, 35, 34, 37, 38, 41, 40, 36, 44, 64, 39, 42, 43, 45, 46, 47, 48, 50, 51, 52, 54, 53, 56, 55, 59, 57, 60, 58, 66, 65, 69, 67, 61, 96
Offset: 0

Views

Author

Rémy Sigrist, Nov 11 2023

Keywords

Comments

This sequence is a variant of A333400; here we combine initial terms with the XOR operator, there with the addition.
This sequence is well defined; after some initial terms we can extend the sequence with a power of 2 greater that any prior term or even a smaller value.
This sequence is a permutation of the nonnegative integers (with inverse A367263):
- for any k >= 0, the least value >= 2^k is precisely 2^k,
- all powers of 2 appear in the sequence,
- after a power of 2, if the least value not yet in the sequence is less than this power of 2, then this value will be the next term.

Examples

			The first terms are:
  n   a(n)  a(0) XOR ... XOR a(n)
  --  ----  ---------------------
   0     0                      0
   1     1                      1
   2     2                      3
   3     4                      7
   4     3                      4
   5     6                      2
   6     7                      5
   7     8                     13
   8     5                      8
   9    14                      6
  10     9                     15
  11    16                     31
  12    10                     21
		

Crossrefs

Cf. A333400, A346298, A367263 (inverse), A367264.
Showing 1-3 of 3 results.