|
| |
|
|
A152735
|
|
Count of links in n-th maximal chain of primes.
|
|
9
| |
|
|
2, 3, 1, 1, 2, 4, 3, 1, 1, 2, 2, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 1, 1, 2, 1, 2, 4, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 6, 1, 4, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 4, 1, 1, 2, 2, 2, 2, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 2, 1
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| One less than count of members of n-th maximal chain of primes. For definitions see A152658.
|
|
|
LINKS
| Klaus Brockhaus, Table of n, a(n) for n=1..1000
|
|
|
EXAMPLE
| The consecutive primes 5, 7, 11 form the first maximal chain of primes (see example in A152658); it has three members, two links. Therefore a(1) = 2.
|
|
|
PROG
| (PARI) {n=1; while(n<560, c=0; while(isprime(n*prime(n)+(n+1)*prime(n+1)), c++; n++); if(c>0, print1(c, ", ")); n++)}
|
|
|
CROSSREFS
| Cf. A152658 (beginnings of maximal chains of primes), A152657 (secluded primes), A119487 (primes of the form i*(i-th prime) + (i+1)*((i+1)-th prime), linking primes).
Sequence in context: A193280 A114732 A123338 * A046226 A054722 A067627
Adjacent sequences: A152732 A152733 A152734 * A152736 A152737 A152738
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Dec 16 2008
|
| |
|
|
