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%I #14 Mar 23 2020 19:15:27
%S 5,8,11,13,15,18,21,23,25,28,31,33,35,38,40,42,44,46,49,52,54,56,58,
%T 60,63,65,67,70,73,75,77,80,82,84,86,88,91,93,95,97,99,102,105,107,
%U 109,111,113,116,118,120,123,126,128,130,132,134,137,139,141,144,146,148,150
%N a(n) = n-th composite + n.
%C Complement of A171511. [_Jaroslav Krizek_, Dec 13 2009]
%H Robert Israel, <a href="/A161537/b161537.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A002808(n) + n = A002808(n) + A000027(n). [_Jaroslav Krizek_, Dec 10 2009]
%e a(1) = composite(1)+1 = 4 +1 = 5 ; a(2) = composite(2)+2 = 6+2=8.
%p Comps:= remove(isprime, [$4..200]):
%p seq(Comps[i]+i,i=1..nops(Comps)); # _Robert Israel_, Mar 23 2020
%t c=0;Do[If[CompositeQ[n],c=c+1;Print[c+n]],{n,1,87}] (* _Metin Sariyar_, Mar 23 2020 *)
%t Range@ Length # + # &@ Select[Range[4, 87], CompositeQ] (* _Michael De Vlieger_, Mar 23 2020 *)
%o (PARI) my(n=0);forcomposite(k=4,86,print1(k+n++,", ")) \\ _Hugo Pfoertner_, Mar 23 2020
%Y Cf. A002808, A171511.
%K nonn
%O 1,1
%A _Claudio Meller_, Jun 13 2009
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