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A240596 Primes of the form p*q*r + 2 where p, q and r are consecutive primes. 5
107, 4201, 18181981, 29884303, 72147193, 81927499, 208506511, 383148631, 402473443, 1106558899, 1391119621, 1459314919, 1498299289, 1945171369, 4593570199, 7908301729, 8052037969, 9970592521, 10594343761, 11304695329, 14119758703, 15111907009, 23157107803 (list; graph; refs; listen; history; text; internal format)
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: A113932 A250154 A250155 * A185677 A262658 A114356

Adjacent sequences:  A240593 A240594 A240595 * A240597 A240598 A240599

KEYWORD

nonn

AUTHOR

K. D. Bajpai, Apr 08 2014

STATUS

approved

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Last modified June 21 16:39 EDT 2021. Contains 345365 sequences. (Running on oeis4.)