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 A087368 Prime-indexed primes (PIPS) whose digits are primes. 1
 3, 5, 277, 353, 773, 3733, 5557, 7523, 7753, 25357, 25733, 27733, 32233, 32323, 32533, 37273, 53233, 53353, 53377, 53777, 55733, 72337, 72727, 73757, 77377, 77557, 232523, 272333, 275773, 322727, 327553, 327757, 333233, 352357, 353527 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,1 COMMENTS Chances are these numbers are infinite since PIPS are infinite. LINKS A. Frank & P. Jacqueroux, International Contest, 2001. Item 12 EXAMPLE 59 is prime, the 59th prime is 277, and 2 and 7 are primes. PROG (PARI) pip(n) = { for(x=1, n, flag=1; y=prime(prime(x)); y2=y; for(j=1, length(Str(y)), r = y%10; if(!isprime(r), flag=0); y = floor(y/10); ); if(flag, print1(y2", ")); ) } CROSSREFS Intersection of A006450 and A046034. Sequence in context: A167483 A101331 A232239 * A309740 A280035 A087670 Adjacent sequences:  A087365 A087366 A087367 * A087369 A087370 A087371 KEYWORD easy,nonn,base AUTHOR Cino Hilliard, Oct 21 2003 STATUS approved

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Last modified April 18 01:28 EDT 2021. Contains 343072 sequences. (Running on oeis4.)