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A030670
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Smallest prime whose decimal expansion begins (nontrivially) with the n-th prime.
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5
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23, 31, 53, 71, 113, 131, 173, 191, 233, 293, 311, 373, 419, 431, 479, 5323, 593, 613, 673, 719, 733, 797, 839, 8923, 971, 1013, 1031, 10711, 1091, 11311, 1277, 1319, 1373, 1399, 1493, 1511, 1571, 1637, 16729, 1733, 17911, 1811, 1913, 1931
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OFFSET
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1,1
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COMMENTS
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Add digits to p (starting with a nonzero digit) until another prime is reached.
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LINKS
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MAPLE
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f:= proc(p) local d, x;
for d from 1 do
x:= nextprime(10^d*p+10^(d-1)-1);
if x < 10^d*(p+1) then return x fi
od
end proc:
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MATHEMATICA
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f[n_] := Block[{k = 1, p = Prime@ n}, While[a = 10^Floor[1 + Log10@ k] p + k; !PrimeQ@ a, k += 2]; a]; Array[f, 44]
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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