cp's OEIS Frontend

A253634 Decimal expansion of Sum_{n>=1} 1/A033286(n)^2.

%I A253634 #26 Oct 30 2022 15:05:49
%S A253634 2,8,4,1,7,0,7,0,5,4,7,0,8,6,8,2,5,0,1,7,7,1,4
%N A253634 Decimal expansion of Sum_{n>=1} 1/A033286(n)^2.
%C A253634 The convergence is very slow, need to use the first 100000000 primes to obtain the correct value of the coefficient of 10^(-23).
%C A253634 The constant is in the interval [0.28417070547086825017714, 0.28417070547086825017743]; these safe limits are computed by accumulating in parallel the partial sum of the lower estimate 1/n^4 = Zeta(4). - _R. J. Mathar_, Feb 06 2015
%e A253634 0.284170705470...
%o A253634 (PFGW & SCRIPT)
%o A253634 SCRIPT
%o A253634 DIM i,0
%o A253634 DIM j,0
%o A253634 DIM n
%o A253634 DIM m
%o A253634 DIMS t
%o A253634 OPENFILEOUT myf,a(n).txt
%o A253634 OPENFILEIN maf,pre.txt
%o A253634 LABEL loop1
%o A253634 SET i,i+1
%o A253634 IF i>10000000 THEN END
%o A253634 GETNEXT n,maf
%o A253634 SET j,j+10^10000/((i*n)^2)
%o A253634 IF i%1000000==0 THEN SET m,j/10^9970
%o A253634 IF i%1000000==0 THEN WRITE myf,m
%o A253634 GOTO loop1
%Y A253634 Cf. A033286 (n*prime(n)), A124012.
%K A253634 nonn,cons,more
%O A253634 0,1
%A A253634 _Pierre CAMI_, Jan 07 2015