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.

A010062 a(0)=1; thereafter a(n+1) = a(n) + number of 1's in binary representation of a(n).

Original entry on oeis.org

1, 2, 3, 5, 7, 10, 12, 14, 17, 19, 22, 25, 28, 31, 36, 38, 41, 44, 47, 52, 55, 60, 64, 65, 67, 70, 73, 76, 79, 84, 87, 92, 96, 98, 101, 105, 109, 114, 118, 123, 129, 131, 134, 137, 140, 143, 148, 151, 156, 160, 162, 165, 169, 173, 178, 182, 187, 193, 196, 199, 204
Offset: 0

Views

Author

Leonid Broukhis, Mar 15 1996

Keywords

Comments

Sequence A230297 (and A157845 without initial term) converted from binary to decimal, cf. formula. - M. F. Hasler, Nov 18 2019

Examples

			a(7) = 14 because a(6) = 12, which is 1100 in binary (having 2 on bits), and 12 + 2 = 14.
a(8) = 17 because a(7) = 14, which is 1110 in binary (having 3 on bits), and 14 + 3 = 17.
		

Crossrefs

First row of A228083.
For the base-10 analog see A004207.
Cf. A000120, A010061, A092391, A229167, A096303, A229743, A229744, A230297 (this sequence written in binary), A230298 (read mod 2).
See A230088 for partial sums.
Equals A028897 o A230297 = A028897 o A157845 (up to offset); see also A007088.

Programs

Formula

a(n) = (n/2)*log n + O(n*sqrt(log n * loglog n)), where log means log_2. In particular, a(n) ~ (n/2)*log n. [Stolarsky]
a(n + 1) = A092391(a(n)) = a(n) + A000120(a(n)). - Reinhard Zumkeller, May 27 2012, May 08 2004; corrected thanks to a notice by Lambert Herrgesell
a(n) = A028897(A230297(n)) = A028897(A157845(n+1)). - M. F. Hasler, Nov 18 2019

Extensions

More terms from Benoit Cloitre, Jun 02 2002
Stolarsky reference from Matthew C. Russell, Oct 08 2013

A096303 Number of iterations of n -> n + (number of 1's in binary representation of n) needed for the trajectory of n to join the trajectory of A010062.

Original entry on oeis.org

0, 0, 0, 1, 0, 4, 0, 3, 2, 0, 1, 0, 2, 0, 1, 1, 0, 2, 0, 1, 6, 0, 2, 5, 0, 4, 1, 0, 3, 2, 0, 3, 2, 1, 1, 0, 5, 0, 2, 4, 0, 3, 1, 0, 2, 7, 0, 7, 1, 6, 1, 0, 5, 3, 0, 2, 4, 2, 1, 0, 3, 1, 6, 0, 0, 2, 0, 1, 5, 0, 2, 4, 0, 3, 1, 0, 2, 5, 0, 5, 1, 4, 1, 0, 3, 10, 0, 2, 2, 9, 1, 0, 1, 8, 1, 0, 8, 0, 7, 7, 0, 6, 6, 6, 0
Offset: 1

Views

Author

Jason Earls, Jun 25 2004

Keywords

Comments

Conjecture: For any positive integer starting value n, iterations of n -> n + (number of 1's in binary representation of n) will eventually join A010062.

Examples

			a(6)=4 because the trajectory for 1 (sequence A010062) starts
1->2->3->5->7->10->12->14->17->19->22->25...
and the trajectory for 6 starts
6->8->9->11->14->17->19->22->25->28->31->36...
so the sequence beginning with 6 joins A010062 after 4 steps.
		

Crossrefs

Cf. A010062.
For records see A229743, A229744.

Programs

  • PARI
    a(n) = { my (o=1); for (k=0, oo, while (oRémy Sigrist, Apr 05 2020

A229744 Values of records in A096303.

Original entry on oeis.org

0, 1, 4, 6, 7, 10, 11, 20, 21, 23, 32, 33, 38, 47, 51, 52, 53, 54, 78, 101, 106, 122, 177, 205, 216, 370, 373, 383, 393, 411, 753, 757, 758, 763
Offset: 1

Views

Author

Matthew C. Russell and Nathan Fox, Oct 06 2013

Keywords

Crossrefs

Extensions

a(15)-a(34) from Donovan Johnson, Oct 07 2013
Showing 1-3 of 3 results.