

A089105


Values taken by least witness function W(n).


4



2, 3, 5, 6, 7, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 26
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,1


COMMENTS

19, 22, 23, 26, 29, 31, 34, 37, 38, 41, 43, 46, and 47 are in this sequence. Is this a duplicate of A007916?  Charles R Greathouse IV, Sep 07 2011
It has because of
 
18 565491872244422701441
20 76786041519852770748961
21 1747624437573692208710761
24 79962397898771029747829041
Alas, those are merely upperbounds on the A089825 values.
(End)
The least witness function W(k) is defined for odd composite numbers k. The sequence W(k) does not have its own entry in the OEIS because W(k) = 2 for all k with 9 <= k < 2047; then W(2047)=3.  N. J. A. Sloane, Sep 16 2014


REFERENCES

R. Crandall and C. Pomerance, Prime Numbers: A Computational Perspective, Springer, NY, 2001; see p. 157 (pp. 168f in the 2nd edition).


LINKS



CROSSREFS



KEYWORD

nonn,hard


AUTHOR



EXTENSIONS



STATUS

approved



