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%I #13 Sep 08 2022 08:45:46
%S 0,0,0,1,2,5,6,9,10,13,18,19,24,27,28,31,36,41,42,47,50,51,56,59,64,
%T 71,74,75,78,79,82,95,98,103,104,113,114,119,124,127,132,137,138,147,
%U 148,151,152,163,174,177,178,181,186,187,196,201,206,211,212,217,220,221
%N a(n) is the number of composite numbers that are smaller than A008578(n).
%C Essentially the same as A065890.
%C a(n) = number of terms of A073169(n) less than n.
%F a(n) = A008578(n) - n = A158611(n+1) -n.
%F a(n) = A065890(n-1) for n > 1.
%e A008578(6) = 11, and there are 5 composites smaller than 11, viz. 4, 6, 8, 9, 10, hence a(6) = 5.
%o (Magma) T:=[0,1] cat PrimesUpTo(300); [ T[n+1]-n: n in [1..#T-1] ]; // _Klaus Brockhaus_, Sep 08 2009
%Y Cf. A002808 (composites), A008578 (1 and the primes), A065890, A073169.
%K nonn,easy
%O 1,5
%A _Jaroslav Krizek_, Jun 27 2009
%E Edited and extended by _Klaus Brockhaus_, Sep 09 2009
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