

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
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OFFSET

0,1


COMMENTS

Decimal expansion of 101/450.
Also list of smallest ncomposites.
A hyperoperator aggregation b[n]c is ncomposite if b,c are positive nonrightidentity elements.
The identity elements are:
Hyper0 (zeration): none.
Hyper1 (addition): 0.
Hyper2 (multiplication): 1.
Hyper3 (exponentiation): 1.
Hypern (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 nonrightidentity elements.


EXAMPLE

a(0) = 2 because 1 is the smallest nonidentity element in zeration and 1[0]1=2;
a(1) = 2 because 1 is the smallest nonidentity element in addition and 1[1]1=2;
a(2) = 4 because 2 is the smallest nonidentity element in multiplication and 2[2]2=4;
a(3) = 4 because 2 is the smallest nonidentity element in exponentiation and 2[2]2=4;
a(4) = 4 because 2 is the smallest nonidentity element in titration and 2[2]2=4;
Etc.


CROSSREFS

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



