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%I #4 Mar 15 2015 09:47:59
%S 2,4,9,5,8,0,6,5,1,4,0,5,9,8,3,8,2,7,2,7,7,4,9,7,9,2,0,4,9,3,0,1,5,3,
%T 4,3,7,2,6,1,0,3,7,9,3,7,6,1,5,5,0,7,7,9,6,3,9,6,9,1,6,5,3,8,9,5,1,3,
%U 5,7,2,2,2,6,4,9,6,5,6,5,6,9,0,4,5,5,5,7,0,3,4,8,5,6,1,3,5,4,0,0,1,6,2,5,2
%N Decimal expansion of Product_p p#/(p#-1).
%C By p# we mean the primorial number which is the product of the primes less than or equal to p.
%F This number is equal to Sum_k 1/A025487(k).
%e 2/1 * 6/5 * 30/29 * ... = 2.495806514059838272774979204930153...
%t RealDigits[Times@@(#/(#-1)&/@Rest[FoldList[Times,1,Prime[Range[100]]]]), 10,120][[1]] (* _Harvey P. Dale_, Mar 15 2015 *)
%o (PARI) h(n)=local(p,pl,r);p=2;pl=1;r=1.;while(p<n,pl*=p;r/=(1-1./pl);p=nextprime(p+1));r
%Y Cf. A002110, A034386, A025487, A064648.
%K cons,nonn
%O 1,1
%A _Franklin T. Adams-Watters_, Jun 07 2009
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