|
| |
|
|
A079141
|
|
Primes of the form p^2 + 6 where p is prime.
|
|
2
| |
|
|
31, 127, 367, 967, 3727, 6247, 7927, 11887, 17167, 22807, 39607, 72367, 109567, 160807, 185767, 323767, 502687, 737887, 863047, 885487, 942847, 982087, 1079527, 1560007, 1739767, 1852327, 1985287, 2105407, 2343967, 2399407
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| Sum of reciprocals = 0.044715...
|
|
|
LINKS
| T. D. Noe, Table of n, a(n) for n=1..1000
|
|
|
MATHEMATICA
| f[n_]:=n^2+6; lst={}; Do[p=Prime[n]; If[PrimeQ[f[p]], AppendTo[lst, f[p]]], {n, 7!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jul 17 2009]
|
|
|
PROG
| (PARI) sqppn(n) = {sr=0; forprime(x=3, n, y = x*x+6; if(isprime(y), print1(y" "); sr+=1.0/y; ); ); print(); print(sr); } \\ Primes of the form p^2 + 6 and the sum of the reciprocals.
|
|
|
CROSSREFS
| Cf. A056909.
Sequence in context: A095322 A127578 A158563 * A049203 A065403 A035502
Adjacent sequences: A079138 A079139 A079140 * A079142 A079143 A079144
|
|
|
KEYWORD
| easy,nonn
|
|
|
AUTHOR
| Cino Hilliard (hillcino368(AT)gmail.com), Dec 26 2002
|
| |
|
|
