The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A083776 The n-th row of the following triangle contains n distinct primes such that the product of (n-1) of them + 2 is prime in all cases. The first (n-1) numbers are the smallest set whose product +2 is a prime and the n-th term is chosen to satisfy the requirement. a(1) = 2 by convention. Sequence contains the triangle by rows. 2
 2, 3, 5, 3, 5, 7, 3, 5, 7, 31, 3, 5, 7, 13, 127, 3, 5, 7, 11, 13, 149, 3, 5, 7, 11, 13, 19, 12653, 3, 5, 7, 11, 13, 17, 31, 92467, 3, 5, 7, 11, 13, 17, 19, 37, 342362509 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Perhaps the sequence is finite in the sense there exists some n for which the n-th term ( the last term ) of the row does not exist. LINKS Table of n, a(n) for n=1..45. EXAMPLE 2 3 5 3 5 7 3 5 7 31 ... PROG (PARI) row(n) = {if(n==1, return([2])); my(c=1, p=prime(n), v=vector(n-2, i, prime(i+1)), w); while(!isprime(vecprod(v)*p+2), p=nextprime(p+1)); v=concat(v, p); w=vector(n-1, i, vecprod(v)/v[i]); while(c

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

Last modified April 21 19:32 EDT 2024. Contains 371885 sequences. (Running on oeis4.)