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 A089778 a(n) is the n-th prime that ends with prime(n), or 0 if there do not exist n primes ending with prime(n). 2
 2, 13, 0, 47, 911, 1213, 2417, 1619, 1723, 2729, 2131, 3137, 4241, 4643, 3947, 4153, 4759, 5861, 4967, 6271, 6173, 6379, 6883, 7589, 7297, 98101, 97103, 104107, 108109, 129113, 130127, 122131, 174137, 136139, 131149, 150151, 172157, 147163 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 EXAMPLE a(5) = 911 because prime(5) = 11 and the first 5 primes ending with 11 are 11, 211, 311, 811 and 911. a(3) = 0 because prime(3) = 5 and only 1 prime ends with 5. MAPLE f:= proc(n) local p, d, k, count; p:= ithprime(n); d:= 10^(ilog10(p)+1); count:= 1; for k from 1 while count < n do    if isprime(k*d+p) then count:= count+1 fi od; (k-1)*d+p end proc: f(3):= 0: map(f, [\$1..100]); # Robert Israel, Dec 10 2017 PROG (PARI) a(n) = if(n == 3, return(0)); my(p = prime(n), d = 10^(logint(p, 10)+1), i = 1); for(x=0, +oo, if(isprime(x*d+p), i++; if(i > n, return(x*d+p)))); \\ Iain Fox, Dec 10 2017 CROSSREFS Sequence in context: A130769 A128033 A090954 * A088253 A249224 A217010 Adjacent sequences:  A089775 A089776 A089777 * A089779 A089780 A089781 KEYWORD base,nonn,easy AUTHOR Amarnath Murthy, Nov 24 2003 EXTENSIONS Corrected and extended by David Wasserman, Oct 12 2005 STATUS approved

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Last modified June 7 02:48 EDT 2020. Contains 334836 sequences. (Running on oeis4.)