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A155740
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Concatenation of prime number n and odd n-th nonprime.
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1
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21, 1725, 1927, 2333, 3751, 79105, 83111, 131169, 167213, 173219, 191243, 193245, 197249, 227287, 229289, 251315, 269335, 307381, 317393, 367453, 379469, 383473, 397489, 419515, 421517, 431529, 433531, 439537, 449549, 463565, 499609, 521635
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| If n=2=prime and nonprime(2)=1=odd nonprime, then concatenate=21=a(1). If n=13=prime and nonprime(13)=21=odd nonprime, then concatenate=1321=a(2). If n=17=prime and nonprime(17)=25=odd nonprime, then concatenate=1725=a(3), etc.
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MAPLE
| Contribution from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 15 2010: (Start)
cat2 := proc(a, b) dgsb := max(1, ilog10(b)+1) ; a*10^dgsb+b ; end proc:
A155740 := proc(n) p := ithprime(n) ; c := A141468(p) ; if type(c, 'odd') then cat2(p, c) ; printf("%d, ", %) ; end if; return ; end proc:
seq(A155740(n), n=1..120) ; (End)
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CROSSREFS
| Cf. A000040, A141468.
Sequence in context: A203361 A192843 A130039 * A203327 A163928 A153848
Adjacent sequences: A155737 A155738 A155739 * A155741 A155742 A155743
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KEYWORD
| nonn,base
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AUTHOR
| Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Jan 26 2009
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EXTENSIONS
| Corrected (1321 removed, all terms >=200000 corrected) by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 15 2010
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