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A048837 Decimal expansion of Sum_{n >= 2} (n^2 / Product_{i=2..n} K(i)), where K(i) is the Kempner function A002034.

%I A048837 #28 Feb 16 2025 08:32:40
%S A048837 4,5,0,2,5,1,2,0,0,6,1,9,2,9,6,9,7,0,6,9,3,4,0,7,7,2,7,4,8,3,2,4,4,5,
%T A048837 6,4,1,9,7,6,5,1,3,1,4,7,4,6,9,1,3,3,3,0,4,1,1,8,9,8,7,5,3,6,5,2,8,0,
%U A048837 8,5,2,7,0,1,5,5,0,1,1,0,6,6,7,3,1,1,1,5,6,3,9,5,2,2,5,6,2,3,1,3
%N A048837 Decimal expansion of Sum_{n >= 2} (n^2 / Product_{i=2..n} K(i)), where K(i) is the Kempner function A002034.
%D A048837 I. Cojocaru, S. Cojocaru, The Third and Fourth Constants of Smarandache, Smarandache Notions Journal, Vol. 7, No. 1-2-3, 1996, 121-126.
%H A048837 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SmarandacheConstants.html">Smarandache Constants</a>
%e A048837 4.5025120061929697...
%o A048837 (PARI)
%o A048837 S(n)=local(m);if(isprime(n),n,m=1;while(m!%n!=0,m++);m)
%o A048837 S4(a,k)=local(v,i,p,y);v=vector(k,i,S(i));p=1;y=0.;for(i=2,k,p*=v[i];y+=i^a/p);y
%o A048837 S4(2,200) \\ _Franklin T. Adams-Watters_, Apr 18 2006
%K A048837 nonn,cons
%O A048837 1,1
%A A048837 Charles T. Le (charlestle(AT)yahoo.com)
%E A048837 More terms from _Franklin T. Adams-Watters_, Apr 18 2006
%E A048837 Name corrected by _Sean A. Irvine_, Jul 10 2021