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A108836
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Primes such that the outer 2 digits are n and n-1 and all inner digits are 8, where 0 < n < 9.
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0
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281, 887, 8887, 48883, 888887, 888888887, 48888888883, 888888888887, 2888888888881, 4888888888883, 48888888888883, 2888888888888888888888888881, 48888888888888888888888888888888888888883
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OFFSET
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1,1
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LINKS
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MATHEMATICA
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Sort[Select[Flatten[Table[FromDigits[Join[{n}, PadRight[{}, k, 8], {n-1}]], {n, 2, 8, 2}, {k, 50}]], PrimeQ]] (* Harvey P. Dale, Mar 08 2023 *)
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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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