|
Search: id:A068489
|
|
|
| A068489 |
|
m for which p(m) is the least prime dividing #p(n) - 1, i.e. one less than primorial n-th prime (A057588). |
|
+0 2
|
|
| 3, 10, 5, 343, 3248, 18, 16, 12, 22, 20324, 50
(list; graph; listen)
|
|
|
OFFSET
|
2,1
|
|
|
COMMENT
|
Since #P13 -1 is a prime, see A006794, we need the number of primes less than or equal to #P13 -1. The sequence continues 13120,43,8481,1200361259,196,38,10326732314,65,38,34,
|
|
LINKS
|
Hisanori Mishima, Factorization results #Pn (Primorial) - 1
|
|
FORMULA
|
PrimePi(A057713)
|
|
MATHEMATICA
|
Do[ Print[ PrimePi[ FactorInteger[ Product[ Prime[k], {k, 1, n}] - 1] [[1, 1]]]], {n, 2, 22} ]
|
|
CROSSREFS
|
Cf. A068488.
Sequence in context: A035411 A033478 A111127 this_sequence A088337 A087397 A033152
Adjacent sequences: A068486 A068487 A068488 this_sequence A068490 A068491 A068492
|
|
KEYWORD
|
hard,more,nonn
|
|
AUTHOR
|
Lekraj Beedassy (blekraj(AT)yahoo.com), Mar 11 2002
|
|
EXTENSIONS
|
Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com), Mar 12 2002
|
|
|
Search completed in 0.002 seconds
|