A288481 Numbers k such that p1 = prime(k) + prime(k+1) + prime(k+2), p2 = p1 + prime(k+3) + prime(k+4), p3 = p2 + prime(k+5) + prime(k+6), p4 = p3 + prime(k+7) + prime(k+8), p5 = p4 + prime(k+9) + prime(k+10), p6 = p5 + prime(k+11) + prime(k+12), p7 = p6 + prime(k+13) + prime(k+14) and p8 = p7 + prime(k+15) + prime(k+16) are all prime

7167305, 20224749, 32848229, 63138028, 98444311, 361075686, 530778019, 541985251, 562407560, 608779540, 678479762, 700368011, 816865538

Offset

1,1

Comments

a(12)=700368011: p9 = p8 + prime(k+17) + prime(k+18) =

298451681831 prime - first such case. - Zak Seidov, Jun 10 2017

Links

Table of n, a(n) for n=1..13.

Prog

(PARI) list(lim)=my(v=List(), u=primes(17), n=1, p1, p3, p4, p5, p6, p7); forprime(s=u[7]+1, , if(n++>lim, break); u=concat(u[2..17], s); if(isprime(p1=u[1]+u[2]+u[3]) && isprime(p2=p1+u[4]+u[5]) && isprime(p3=p2+u[6]+u[7]) && isprime(p4=p3+u[8]+u[9]) && isprime(p5=p4+u[10]+u[11]) && isprime(p6=p5+u[12]+u[13]) && isprime(p7=p6+u[14]+u[15]) && isprime(p7+u[16]+u[17]), listput(v, n))); Vec(v) \\ Charles R Greathouse IV, Jun 10 2017

Crossrefs

Subsequence of A288107.

Sequence in context: A137599 A151937 A204308 * A286010 A184214 A181680

Adjacent sequences: A288478 A288479 A288480 * A288482 A288483 A288484

Keyword

nonn,more

Author

Zak Seidov, Jun 09 2017

Extensions

a(6)-a(13) from Charles R Greathouse IV, Jun 10 2017

Status

approved