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 A105347 Concatenation of the largest and the smallest n-digit primes (in that order). 0
 72, 9711, 997101, 99731009, 9999110007, 999983100003, 99999911000003, 9999998910000019, 999999937100000007, 99999999671000000007, 9999999997710000000019, 999999999989100000000003 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Chris Caldwell, The First 10,000 Primes. EXAMPLE The largest and smallest 1-digit primes are 7 and 2, so the first term is 72. The largest and smallest 2-digit primes are 97 and 11, so the second term is 9711. MAPLE for n from 0 to 30 do for m from 1 to 10^(n+1)-1 do if isprime(10^(n+1) - m) then printf(`%d`, 10^(n+1)-m); break; fi: od: for m from 1 to 10^(n+1)-1 do if isprime(10^n + m) then printf(`%d`, 10^n+m); break; fi: od: printf(`, `): od: # James A. Sellers, May 02 2005 CROSSREFS Cf. A104206. Sequence in context: A178635 A271189 A093272 * A093236 A146500 A271190 Adjacent sequences:  A105344 A105345 A105346 * A105348 A105349 A105350 KEYWORD nonn,base AUTHOR Parthasarathy Nambi, Apr 30 2005 EXTENSIONS More terms from James A. Sellers, May 02 2005 Offset corrected by Michel Marcus, Aug 18 2017 STATUS approved

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Last modified February 27 01:52 EST 2020. Contains 332299 sequences. (Running on oeis4.)