

A339580


Indices of records in A339579.


2




OFFSET

1,2


COMMENTS

The records themselves begin 4,5,6,7,8,9,10,12,13,14.
a(11) <= 90616211958465842220.


REFERENCES

Carl Pomerance, Problem 81:21 (= 321), in R. K. Guy problem list.


LINKS

Table of n, a(n) for n=1..10.
R. K. Guy, editor, Western Number Theory Problems, 19851221 & 23, Typescript, Jul 13 1986, Dept. of Math. and Stat., Univ. Calgary, 11 pages. Annotated scan of pages 1, 3, 7, 9, with permission.


FORMULA

a(n) = A339581(n) + 1 for n >= 2.  David A. Corneth, Dec 24 2020


EXAMPLE

90 is in the sequence as A339579(90) = 6 (90*2^k  1 is prime for k = 0..5 and composite for k = 6) and A339579(m) < 6 for m < 90.  David A. Corneth, Dec 24 2020


CROSSREFS

Cf. A063377, A124514, A125113, A339579, A339581.
Sequence in context: A053996 A218143 A203477 * A115704 A066751 A115886
Adjacent sequences: A339577 A339578 A339579 * A339581 A339582 A339583


KEYWORD

nonn,more


AUTHOR

N. J. A. Sloane, Dec 24 2020


EXTENSIONS

a(8)a(10) were taken from A057331 and the bound on a(11) was taken from A005602.  David A. Corneth and Amiram Eldar, Dec 25 2020


STATUS

approved



