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%I #7 Feb 18 2019 16:55:42
%S 18,181,1811,18119,181193,1811939
%N a(n+1) is the smallest prime formed by appending a single digit to a(n); a(1)=18.
%C There is no prime a(7) since 18119390 to 18119399 are all composite.
%e a(1)=18,
%e a(2)=181,
%e a(3)=1811,
%e a(4)=18119,
%e a(5)=181193,
%e a(6)=1811939. [Corrected by _Jon E. Schoenfield_, Feb 18 2019]
%p A160954 :=proc(n) option remember ; local d; if n =1 then 18; else for d from 1 to 9 by 2 do if isprime(10*prochame n+d) then RETURN(10*procnam n+d 0 ; fi; end:
%p seq(A160954(n), n=1..10) ; _R. J. Mathar_, May 26 2009
%Y Cf. A000040, A160751, A160955.
%K nonn,base,easy,fini,full
%O 1,1
%A _Juri-Stepan Gerasimov_, May 31 2009
%E Redundant part of the definition removed by _R. J. Mathar_, May 21 2010
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