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A069691
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Smallest prime with internal digits = n; or 0 if no such number exists.
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5
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101, 113, 127, 131, 149, 151, 163, 173, 181, 191, 1103, 1117, 1123, 2131, 2141, 1151, 1163, 1171, 1181, 1193, 1201, 1213, 1223, 1231, 1249, 1259, 2267, 1277, 1283, 1291, 1301, 1319, 1321, 2333, 2341, 2351, 1361, 1373, 1381, 1399, 1409, 2411, 1423, 1433
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,1
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COMMENTS
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By placing one digit on both sides of n one get 36 different numbers that might be primes ( 1 to 9 on left and 1,3,7,9 on right). If none of these numbers is a prime then a(n) = 0.
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LINKS
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EXAMPLE
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a(25) = 1259 is prime with internal digits =25.
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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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EXTENSIONS
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STATUS
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approved
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