A138400 Ennea-primes: primes that are the sum of nine consecutive primes, with the first, third, sixth and eighth twin primes.

38261, 5639533, 16575101, 19521091, 22364431, 82787233, 86405131, 150649753, 191162611, 196530679, 208092607, 210650257, 246934183, 280708297, 302537089, 324315349, 398477927, 521460521, 589499399, 718022411, 734674597, 748523207

Offset

1,1

Links

Table of n, a(n) for n=1..22.

Example

{4229,4231} {4241,4243} {4253} {4259,4261} {4271,4273} Sum = 38261.

Mathematica

a={}; Do[p0=Prime[n]; a1=Prime[n-4]; a2=Prime[n-3]; b1=Prime[n-2]; b2=Prime[n-1]; c1=Prime[n+1]; c2=Prime[n+2]; d1=Prime[n+3]; d2=Prime[n+4]; sp=a1+a2+b1+b2+p0+c1+c2+d1+d2; If[PrimeQ[sp]&&a2-a1==2&&b2-b1==2&&c2-c1==2&&d2-d1==2, AppendTo[a, sp]], {n, 5, 10^6}]; a

Prog

(PARI) forprime(p=2, 4e9, if(!isprime(p+2), next); n=nextprime(p+4); if(!isprime(n+2), next); middle=nextprime(n+4); n=nextprime(middle+2); if(!isprime(n+2), next); n=nextprime(n+4)+2; if(!isprime(n), next); s=0; forprime(q=p, n, s+=q); if(isprime(s), print1(s", ")))

Crossrefs

Sequence in context: A068077 A094427 A298427 * A248690 A342960 A050777

Adjacent sequences: A138397 A138398 A138399 * A138401 A138402 A138403

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, May 08 2008

Extensions

Extended and edited by Charles R Greathouse IV, Nov 03 2009

Status

approved