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%I #8 Jun 30 2024 03:31:40
%S 0,8,169,2371,25059,655974,57509995,1616756446,28550646649,
%T 442195486325,-2830020810398,208945571225276,11214798494956489,
%U 307494657722438109,8565236469871178577
%N Number of primes < 10^(2n) - sum of primes < 10^n.
%C Pi(x) is the prime counting function or the number of primes <= x. SumP(x) = sum of primes <= x.
%C For 2n = 20, we get a negative value -2830020810398. This seems strange to me.
%C I emailed Marc Deleglise on this. The links shows the Pi(x) and SumP(x) values.
%H Cino Hilliard, <a href="http://docs.google.com/Doc?docid=dgpq9w4b_27fmg8k2fk&hl=en">Comparison of Pi(x^2) and SumP(x)</a>. [broken link]
%F a(n) = A006880(2*n) - A046731(n). - _Amiram Eldar_, Jun 30 2024
%Y Cf. A000720, A006880, A046731.
%K sign,more
%O 0,2
%A _Cino Hilliard_, Jun 11 2008
%E a(12)-a(14) from _Amiram Eldar_, Jun 30 2024