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

%I #9 Dec 25 2023 17:36:22

%S 30,70,22,2002,3094,4522,6118,7714,5500082,203503034,8343624394,

%T 358775848942,16862464900274,19015119993926,52728927743156798,

%U 3216464592332564678,215503127686281833426,15300722065726010173246,1116952710797998742646958,1208757043192354803686434

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

%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 1,1

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