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A354221 a(n) is the numerator of the sum of reciprocals of the 2*n+1 consecutive primes starting with A353534(n).

%I A354221 #18 May 31 2022 06:49:07
%S A354221 31,2927,24749279,52404847006669763041,264723826652711,
%T A354221 25709009860910962769666716861,31275582984007762166936591,
%U A354221 9357116090687897728867556889841,13585328068403621603022853,4395564666287059721647967305937566473834609232641255659809,15360643606799479140185671512081451
%N A354221 a(n) is the numerator of the sum of reciprocals of the 2*n+1 consecutive primes starting with A353534(n).
%H A354221 Robert Israel, <a href="/A354221/b354221.txt">Table of n, a(n) for n = 1..122</a>
%e A354221 a(3) = 24749279 because A353534(3) = 5 and 1/5 + 1/7 + 1/11 + 1/13 + 1/17 + 1/19 + 1/23 = 24749279/37182145.
%p A354221 f:= proc(n) local i,k,v;
%p A354221    for k from 1 do
%p A354221      v:= numer(add(1/ithprime(i),i=k..k+2*n));
%p A354221      if isprime(v) then return v fi
%p A354221    od
%p A354221 end proc:
%p A354221 map(f, [$1..30]);
%Y A354221 Cf. A353534.
%K A354221 nonn
%O A354221 1,1
%A A354221 _J. M. Bergot_ and _Robert Israel_, May 29 2022