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%I #10 Mar 24 2021 05:59:06
%S 0,83,0,887,811,88813,88817,8819,823,829,8831,8837,88888841,88843,
%T 88888888888888888888888888888847,853,859,8861,8867,888871,88873,
%U 88888879,883,88888888888889,88897,8101,888103,8888107,888109
%N Smallest prime of the form: all eights followed by prime(n). a(n)> prime(n). 0 if no such prime exists.
%C Prime(n) is all zeros followed by prime(n). This is all eights followed by prime(n). Conjecture: a(n) is nonzero if n > 3.
%e a(4) = 887, as 87 is composite, prime(4) = 7.
%p cat2 := proc(a,b) a*10^(max(1,ilog10(b)+1))+b ; end: A002282 := proc(n) 8*(10^n-1)/9 ; end: A113890 := proc(n) local p,a,n8 ; p := ithprime(n) ; for n8 from 1 to 120 do a := cat2(A002282(n8),p) ; if isprime(a) then return(a) ; fi ; od: RETURN(0) ; end: seq(A113890(n),n=1..35) ; # _R. J. Mathar_, Jan 31 2008
%Y Cf. A113884, A114785, A113886, A113887, A085074, A114789.
%K base,nonn
%O 1,2
%A _Amarnath Murthy_, Nov 18 2005
%E More terms from _R. J. Mathar_, Jan 31 2008
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