|
| |
|
|
A138758
|
|
Index of A001203(n) (continued fraction for pi) in A000040 (primes), or 0 if A001203(n) is not prime.
|
|
3
| |
|
|
2, 4, 0, 0, 0, 0, 0, 0, 1, 0, 2, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0, 2, 6, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 2, 3, 0, 0, 0, 0, 0, 4, 0, 1, 2, 4, 0, 1, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 3, 1, 1, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 2, 0, 1, 0, 0, 0, 1, 3, 0, 0, 1
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
FORMULA
| a(n) = A000720(A001203(n)) * A010051(A001203(n))
|
|
|
EXAMPLE
| This sequence starts 2,4,0,0,... since the first and 2nd terms of the continued fraction expansion of Pi, A001203 = (3, 7, 15, 1,...) are the 2nd resp. 4th primes, while the next two terms are not primes.
|
|
|
PROG
| (PARI) default(realprecision, 1000); t=contfrac(Pi); vector(#t, i, isprime(t[i])*primepi(t[i]))
|
|
|
CROSSREFS
| Cf. A001203, A138757, A138759, A005042.
Sequence in context: A139627 A166926 A028573 * A107501 A126732 A028586
Adjacent sequences: A138755 A138756 A138757 * A138759 A138760 A138761
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| M. F. Hasler (www.univ-ag.fr/~mhasler), Mar 31 2008
|
| |
|
|
