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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A267649 a(1) = a(2) = 2 then a(n) = 4 for n>2. 0
2, 2, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Decimal expansion of 101/450.

Also list of smallest n-composites.

A hyperoperator aggregation b[n]c is n-composite if b,c are positive non-right-identity elements.

The identity elements are:

Hyper-0 (zeration): none.

Hyper-1 (addition): 0.

Hyper-2 (multiplication): 1.

Hyper-3 (exponentiation): 1.

Hyper-n (n>2): 1.

For more information on hyperoperations see A054871.

LINKS

Table of n, a(n) for n=0..101.

FORMULA

a(n) = a[n]b where a,b are the positive smallest non-right-identity elements.

EXAMPLE

a(0) = 2 because 1 is the smallest non-identity element in zeration and 1[0]1=2;

a(1) = 2 because 1 is the smallest non-identity element in addition and 1[1]1=2;

a(2) = 4 because 2 is the smallest non-identity element in multiplication and 2[2]2=4;

a(3) = 4 because 2 is the smallest non-identity element in exponentiation and 2[2]2=4;

a(4) = 4 because 2 is the smallest non-identity element in titration and 2[2]2=4;

Etc.

CROSSREFS

Cf. A000027 (1-composites), A002808 (composites), A267647 (3-composites), A097374 (4-composites).

Sequence in context: A065285 A302437 A179932 * A071805 A063511 A283207

Adjacent sequences:  A267646 A267647 A267648 * A267650 A267651 A267652

KEYWORD

nonn,easy,cons

AUTHOR

Natan Arie' Consigli, Jan 19 2016

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 21 22:17 EDT 2019. Contains 327284 sequences. (Running on oeis4.)