|
Search: id:A062291
|
|
|
| A062291 |
|
Primes p = p(k) such that k * p - 1 is also a prime. |
|
+0
1
|
|
| 3, 19, 37, 43, 61, 113, 251, 317, 359, 409, 463, 491, 557, 601, 683, 827, 863, 941, 1061, 1097, 1109, 1213, 1283, 1291, 1399, 1423, 1481, 1583, 1657, 1693, 1699, 1811, 2069, 2267, 2297, 2531, 2687, 2741, 2851, 3011, 3181, 3271, 3323, 3331, 3347, 3373
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
LINKS
|
Harry J. Smith, Table of n, a(n) for n=1,...,1000
|
|
EXAMPLE
|
19 is the 8th prime and 8*19-1 = 151 is a prime.
|
|
MATHEMATICA
|
Select[ Prime[ Range[ 500 ] ], PrimeQ[ # PrimePi[ # ]-1 ]& ]
|
|
PROGRAM
|
(PARI) for(n=1, 200, if(isprime(n*prime(n)-1), print(prime(n))))
(PARI) { n=k=0; forprime (p=2, 5*10^5, k++; if (isprime(k*p - 1), write("b062291.txt", n++, " ", p); if (n==1000, break)) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 04 2009]
|
|
CROSSREFS
|
Sequence in context: A061427 A069516 A098856 this_sequence A106082 A088786 A147237
Adjacent sequences: A062288 A062289 A062290 this_sequence A062292 A062293 A062294
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Jason Earls (zevi_35711(AT)yahoo.com), Jul 02 2001
|
|
EXTENSIONS
|
More terms from Harvey P. Dale (hpd1(AT)nyu.edu), Jul 05 2001
|
|
|
Search completed in 0.002 seconds
|
