login
This site is supported by donations to The OEIS Foundation.

 

Logo

Annual Appeal: Please make a donation (tax deductible in USA) to keep the OEIS running. Over 5000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A156253 Least k such that A054353(k)>=n 7
1, 2, 2, 3, 3, 4, 5, 6, 6, 7, 8, 8, 9, 9, 10, 11, 11, 12, 12, 13, 14, 15, 15, 16, 17, 18, 18, 19, 19, 20, 21, 21, 22, 23, 24, 24, 25, 26, 26, 27, 27, 28, 29, 30, 30, 31, 32, 33, 33, 34, 35, 35, 36, 36, 37, 38, 38, 39, 39, 40, 41, 42, 42, 43, 44, 44, 45, 45, 46, 47, 47, 48, 49, 50 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n)=1 plus the number of symbol changes in the first n terms of A000002. [From Jean-Marc Fedou and Gabriele Fici, Mar 18 2010]

LINKS

Table of n, a(n) for n=1..74.

J.M. Fedou and G. Fici, Some remarks on differentiable sequences and recursivity, Journal of Integer Sequences 13(3): Article 10.3.2 (2010).

FORMULA

a(n) should be asymptotic to 2n/3.

Length of n-th run of the sequence = A000002(n) [From Benoit Cloitre, Feb 19 2009]

MATHEMATICA

a2 = {1, 2, 2}; Do[ a2 = Join[a2, {1 + Mod[n - 1, 2]}], {n, 3, 80}, {i, 1, a2[[n]]}]; a3 = Accumulate[a2]; a[1] = 1; a[n_] := a[n] = For[k = a[n - 1], True, k++, If[a3[[k]] >= n, Return[k]]]; Table[a[n], {n, 1, 80}] (* Jean-Fran├žois Alcover, Jun 18 2013 *)

CROSSREFS

Sequence in context: A255573 A062298 A116579 * A265436 A060151 A097330

Adjacent sequences:  A156250 A156251 A156252 * A156254 A156255 A156256

KEYWORD

nonn,changed

AUTHOR

Benoit Cloitre, Feb 07 2009

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified December 6 03:18 EST 2016. Contains 278772 sequences.