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Continued fraction for the decimal expansion of the concatenation of the terms of A051699 (distance from n to closest prime).
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%I #30 Jun 21 2019 15:36:26

%S 0,4,1,3,5,9,1,2,2,4,7,1,246,1,2,2,1,116363868,3,1,1,1,3,4,282,1,1,1,

%T 2,1,8,2,1,1,1,1,7,10,7,1,2,1,6,2,1,2,7,2,11,1,3,1,4,1,4,1,3,5,9,1,1,

%U 1,3,3,1,3,2,1,5,3,3,1,32,1,1,15,3,1,1,11,9,1

%N Continued fraction for the decimal expansion of the concatenation of the terms of A051699 (distance from n to closest prime).

%C Continued fraction for .2100101012101012101012101232101012321... (see A051699).

%C Very high value for a(17) = 116363868. This should imply that using the first 16 terms we have a good rational approximation of this decimal expansion: 131256182/624999375 is ok up to the 25th decimal digit.

%p Digits:=200: with(numtheory): P:=proc(q) local a,b,n; a:=21;

%p for n from 2 to q do if isprime(n) then a:=10*a; else

%p b:=min(nextprime(n)-n,n-prevprime(n)); a:=a*10^length(b)+b; fi; od;

%p op(convert(evalf(a/10^length(a)),confrac,100)); end: P(200);

%Y Cf. A030168, A051699.

%K base,cofr,nonn,easy

%O 0,2

%A _Paolo P. Lava_, Jun 17 2019