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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A087088 If all the 1's are removed the sequence is the same as the original with every term one greater than before. It is the simplest nontrivial sequence with this property. 2
1, 2, 3, 1, 4, 2, 1, 5, 3, 1, 2, 6, 1, 4, 2, 1, 3, 7, 1, 2, 5, 1, 3, 2, 1, 4, 8, 1, 2, 3, 1, 6, 2, 1, 4, 3, 1, 2, 5, 1, 9, 2, 1, 3, 4, 1, 2, 7, 1, 3, 2, 1, 5, 4, 1, 2, 3, 1, 6, 2, 1, 10, 3, 1, 2, 4, 1, 5, 2, 1, 3, 8, 1, 2, 4, 1, 3, 2, 1, 6, 5, 1, 2, 3, 1, 4, 2, 1, 7, 3, 1, 2, 11, 1, 4, 2, 1, 3, 5, 1, 2, 6, 1, 3, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

COMMENTS

To construct the sequence: Step 1: start from a sequence of 1 and leave 2 undefined places between two 1 giving: 1,(),(),1,(),(),1,(),(),1,(),(),1,(),(),1,... Step 2: replace the first undefined place with a 2 and leave 2 undefined places between two 2 giving: 1,2,(),1,(),2,1,(),(),1,2,(),1,(),2,1,... Step 3: replace the first undefined place with a 3 and leave 2 undefined places between two 3 giving: 1,2,3,1,(),2,1,(),3,1,2,(),1,(),2,1,... Step 4: replace the first undefined place with a 4 and leave 2 undefined places between two 4 giving: 1,2,3,1,4,2,1,(),3,1,2,(),1,4,2,1,... Iterating the process indefinitely yields the sequence: 1,2,3,1,4,2,1,5,3,1,2,6,1,4,2,1,... [From Benoit Cloitre, Mar 07 2009]

LINKS

Alois P. Heinz, Table of n, a(n) for n = 3..10000

FORMULA

a(n)=1 when n=1(Mod 3), else a(n)=a(n-ceil(n/3))+1.

a(n) = 3 + A244040(3*(n-1)) - A244040(3*n). - Tom Edgar and James Van Alstine, Aug 04 2014

CROSSREFS

Cf. A001511, A244040.

Records are given by A061419: a(A061419(n))=n, where A061419(n) = ceiling(A061419(n-1)*3/2).

Sequence in context: A214967 A195164 A223025 * A255250 A273620 A104705

Adjacent sequences:  A087085 A087086 A087087 * A087089 A087090 A087091

KEYWORD

nonn,easy

AUTHOR

Enrico T. Federighi (rico125162(AT)aol.com), Aug 08 2003

EXTENSIONS

More terms from Paul D. Hanna, Aug 21 2003

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 February 20 08:27 EST 2018. Contains 299377 sequences. (Running on oeis4.)