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A108831
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Primes such that the outer 2 digits are n and n-1 and all inner digits are 4, where 0 < n < 9.
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0
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241, 443, 2441, 8447, 444443, 844447, 2444441, 444444443, 244444444441, 444444444443, 444444444444444444444444444443, 2444444444444444444444444444441, 44444444444444444444444444444443
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OFFSET
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1,1
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LINKS
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PROG
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(PARI) n10np1(n, d) = { local(x, y, k); for(x=1, n, for(k=1, 8, y=10^(x+1)*k+floor(10^x*d/9)*10+k-1; if(isprime(y), print1(y", ")) ) ) }
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CROSSREFS
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KEYWORD
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easy,nonn,base
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AUTHOR
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STATUS
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approved
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