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A108826 Primes such that the outer 2 digits are n and n+1 and all inner digits are 8, where 0 < n < 9. 0
283, 28888883, 88888888888889, 88888888888888889, 28888888888888888888888888883, 6888888888888888888888888888888887, 88888888888888888888888888888888889 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

FORMULA

a(x) = 10^(x+1)*n+floor(10^x*8/9)*10+n+1. Output if a(x) is prime.

PROG

(PARI) n10np1(n) = { local(x, y, k); for(x=1, n, for(k=1, 8, y=10^(x+1)*k+floor(10^x*8/9)*10+k+1; if(isprime(y), print1(y", ")) ) ) }

CROSSREFS

Sequence in context: A059257 A142837 A064964 * A061310 A092681 A090789

Adjacent sequences:  A108823 A108824 A108825 * A108827 A108828 A108829

KEYWORD

easy,nonn,base

AUTHOR

Cino Hilliard (hillcino368(AT)gmail.com), Jul 11 2005

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Last modified February 16 04:47 EST 2012. Contains 205860 sequences.