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%I #11 Mar 11 2014 01:34:14
%S 0,0,0,0,2,0,2,0,2,2,4,0,4,2,2,2,6,2,6,2,4,4,6,0,6,6,6,4,8,2,8,4,6,6,
%T 6,2,10,8,8,4,10,4,10,6,6,8,10,2,10,8,10,8,12,6,10,6,10,10,12,2,12,10,
%U 8,8,12,8,14,10,12,8,14,4,14,12,10,10,12,8,14,6,12,14,16,6,14,14,14,10,16,6
%N a(n) = A161205(n)-A000005(n).
%C It appears that a(n)= 0 if and only if n divides 24 (See also the comments in A018253).
%H Omar E. Pol, <a href="http://www.polprimos.com">Determinacion geometrica de los numeros primos y perfectos</a>
%H Omar E. Pol, <a href="http://www.polprimos.com/imagenespub/polprdipi.jpg">Illustration: Divisors and pi(x)</a>
%F a(n) = 2*(A000196(n) - A038548(n)) = 2*A236627(n). - _Omar E. Pol_, Feb 05 2014
%Y Cf. A000005, A000720, A018253, A160811, A161205.
%K easy,nonn
%O 1,5
%A _Omar E. Pol_, Jun 19 2009
%E Edited by _Omar E. Pol_, Aug 02 2009
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