This site is supported by donations to The OEIS Foundation.

 Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS". Other ways to donate

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A079139 Numbers n such that (Product of first n twin prime pair averages [A014574] ) + 1 is prime. 1
 1, 5, 45, 218, 506, 538 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS a(3) and a(4) certified prime with Primo. LINKS EXAMPLE a(2)=5 because the product of the first five terms of A014574 + 1, 4*6*12*18*30+1 = 155521, is prime. PROG (PARI) { atp(N)= local(t, c); t=1; c=0; forprime(p=2, N, if(isprime(p+2), t*=p+1; c++; if(isprime(t+1), print1(c" ")))) } CROSSREFS Cf. A014574. Sequence in context: A003185 A201876 A027801 * A269911 A249638 A188349 Adjacent sequences:  A079136 A079137 A079138 * A079140 A079141 A079142 KEYWORD more,nonn AUTHOR Jason Earls (zevi_35711(AT)yahoo.com), Dec 26 2002 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.