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A108822 Primes such that the outer 2 digits are n and n+1 and all inner digits are 5, where 0 < n < 9. 0
859, 65557, 855555559, 6555555557, 855555555555555559, 85555555555555555559, 6555555555555555555557, 85555555555555555555555559, 85555555555555555555555555555555555555559 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

FORMULA

a(x) = 10^(x+1)*n+floor(10^x*5/9)*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*5/9)*10+k+1; if(isprime(y), print1(y", ")) ) ) }

CROSSREFS

Sequence in context: A163304 A183628 A187281 * A115749 A105323 A206756

Adjacent sequences:  A108819 A108820 A108821 * A108823 A108824 A108825

KEYWORD

easy,nonn,base

AUTHOR

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

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Last modified February 17 03:45 EST 2012. Contains 205978 sequences.