[seqfan] Re: subset (base) of A167676: emirps which are concatenations of three consecutive primes

[Maximilian Hasler]

Oops, there were two "))" missing in my PARI code.

On Tue, Nov 10, 2009 at 5:41 PM, Jonathan Post <jvospost3 at gmail.com> wrote:
> Well, no more through A167676(22).  I am the #4 contributor to Prime
> Curios, and already submitted  353359367.

Below you have some of the smallest: (takes ~ 0.3 sec to compute,
could of course be highly optimized...)

Maximilian

for(i=1,1999, isprime(eval(p=Str(prime(i),prime(i+1),prime(i+2)))) &
isprime(eval(concat(vecextract(Vec(p),"-1..1"))))& print1(p,", "))

353359367, 193319491951, 334733593361, 344934573461, 346734693491,
732173317333, 902990419043, 104591046310477, 133091331313327,
141591417314177, 146571466914683, 150131501715031, 154431545115461,
171371715917167, 171671718317189, 186711867918691, 312593126731271,
322513225732261, 323093232132323, 324293244132443, 335333354733563,
338113382733829, 339973401934031, 348413484334847, 348433484734849,
354613549135507, 367213673936749, 369313694336947, 371993720137217,
395413955139563, 714197142971437, 714537147171473, 717137171971741,
744137441974441, 744197444174449, 771417715377167, 795497955979561,
913039130991331, 922279223392237, 943079430994321, 957919580195803,
961999621196221, 964879649396497, 967639676996779, 984439845398459,
988939889798899, 999719998999991, 101173101183101197,
103087103091103093,