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Numerator of Sum_{i=1..n} 1/(prime(i)*prime(i+1)*prime(i+2)).
5

%I #14 Dec 25 2023 17:36:08

%S 1,3,1,93,145,213,289,365,260511,9645025,395623447,17017308303,

%T 800016993275,902324346127,2502504187659113,152669617912106167,

%U 10229758110750827711,726365554791051924279,53027901964339123037045,57389311757677767147397

%N Numerator of Sum_{i=1..n} 1/(prime(i)*prime(i+1)*prime(i+2)).

%H Robert Israel, <a href="/A241191/b241191.txt">Table of n, a(n) for n = 1..361</a>

%e 1/30, 3/70, 1/22, 93/2002, 145/3094, 213/4522, 289/6118, 365/7714, 260511/5500082, 9645025/203503034, 395623447/8343624394, 17017308303/358775848942, 800016993275/16862464900274, 902324346127/19015119993926, ...

%p g:= n-> add(1/(ithprime(i)*ithprime(i+1)*ithprime(i+2)),i=1..n);

%p t1:=[seq(g(n),n=1..20)];

%p t1a:=map(numer,t1); # A241191

%p t1b:=map(denom,t1); # A241192

%Y Cf. A024451/A002110, A241189/A241190, A241191/A241192.

%K nonn,frac

%O 1,2

%A _N. J. A. Sloane_, Apr 25 2014, based on a suggestion from _Timothy Varghese_.