A240596 Primes of the form p*q*r + 2 where p, q and r are consecutive primes.

107, 4201, 18181981, 29884303, 72147193, 81927499, 208506511, 383148631, 402473443, 1106558899, 1391119621, 1459314919, 1498299289, 1945171369, 4593570199, 7908301729, 8052037969, 9970592521, 10594343761, 11304695329, 14119758703, 15111907009, 23157107803

Offset

1,1

Comments

All the terms in the sequence, except a(1), are congruent to 1 mod 6.

Links

K. D. Bajpai, Table of n, a(n) for n = 1..3525

Example

107 is prime and appears in the sequence because 107 = (3*5*7)+2.
4201 is prime and appears in the sequence because 4201 = (13*17*19)+2.

Maple

KD := proc() local a, b; a:=ithprime(n)*ithprime(n+1)*ithprime(n+2); b:=a+2; if isprime(b) then RETURN (b); fi; end: seq(KD(), n=1..1000);

Mathematica

Select[Table[Prime[k]*Prime[k+1]*Prime[k+2]+2, {k, 1, 300}], PrimeQ]
Select[Times@@@Partition[Prime[Range[600]], 3, 1]+2, PrimeQ] (* Harvey P. Dale, Nov 21 2018 *)

Prog

(PARI) s=[]; for(k=1, 1000, t=prime(k)*prime(k+1)*prime(k+2)+2; if(isprime(t), s=concat(s, t))); s \\ Colin Barker, Apr 09 2014

Crossrefs

Cf. A000040, A048880, A051507.

Sequence in context: A357551 A250154 A250155 * A185677 A262658 A114356

Adjacent sequences: A240593 A240594 A240595 * A240597 A240598 A240599

Keyword

nonn

Author

K. D. Bajpai, Apr 08 2014

Status

approved