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A105184
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Primes that can be written as concatenation of two primes in decimal representation.
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9
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23, 37, 53, 73, 113, 137, 173, 193, 197, 211, 223, 229, 233, 241, 271, 283, 293, 311, 313, 317, 331, 337, 347, 353, 359, 367, 373, 379, 383, 389, 397, 433, 523, 541, 547, 571, 593, 613, 617, 673, 677, 719, 733, 743, 761, 773, 797, 977, 1013, 1033, 1093
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Primes that can be written as the concatenation of two distinct primes is the same sequence.
Number of terms < 10^n: 0, 4, 48, 340, 2563, 19019, 147249,... [From T. D. Noe (noe(AT)sspectra.com), Oct 04 2010]
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..10000
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MATHEMATICA
| nn=10^4; Union[Reap[Do[p=Prime[i]; q=Prime[j]; n=FromDigits[Join[IntegerDigits[p], IntegerDigits[q]]]; If[PrimeQ[n], Sow[n]], {i, PrimePi[nn/10]}, {j, 2, PrimePi[nn/10^Ceiling[Log[10, Prime[i]]]]}]][[2, 1]]] [From T. D. Noe (noe(AT)sspectra.com), Oct 04 2010]
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CROSSREFS
| Subsequence of A019549.
Cf. A121608, A121609, A121610, A019549, A083427.
Sequence in context: A057878 A019549 A129800 * A066064 A163759 A190731
Adjacent sequences: A105181 A105182 A105183 * A105185 A105186 A105187
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KEYWORD
| nonn,base
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AUTHOR
| Lekraj Beedassy (blekraj(AT)yahoo.com), Apr 11 2005
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EXTENSIONS
| Corrected and extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Apr 16 2005
Edited by N. J. A. Sloane (njas(AT)research.att.com), May 03 2007
Edited by N. J. A. Sloane (njas(AT)research.att.com), to remove erroneous b-file, comments and Mma program, Oct 04 2010
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