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%I #10 Mar 10 2019 01:43:52
%S 6,11,14,12,17,27,23,23,30,38,41,31,35,59,30,41,39,55,71,62,47,53,47,
%T 90,59,55,89,95,83,77,71,123,56,92,71,97,119,71,119,79,89,167,95,103,
%U 126,83,143,125,95,143,194,113,123,139,95,167,185,120,125,223,107,131,119,179
%N The n-th composite plus the sum of its nontrivial divisors.
%C Trivial divisors of a number are 1 and the number itself, see A048050.
%H Harvey P. Dale, <a href="/A163871/b163871.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A002808(n) + A062825(n+1).
%e a(1) = 4 + 2 = 6;
%e a(2) = 6 + 5 = 11;
%e a(3) = 8 + 6 = 14.
%p A002808 := proc(n) local resul,i ; i := 1 ; resul := 4 ; while i < n do resul := resul+1 ; while isprime(resul) do resul := resul+1 ; od ; i := i+1 ; od; RETURN(resul) ; end:
%p A048050 := proc(n) if n <= 3 then 0; else numtheory[sigma](n)-n-1 ; fi; end:
%p A163871 := proc(n) A002808(n)+A048050(A002808(n)) ; end: seq(A163871(n),n=1..80) ; # _R. J. Mathar_, Aug 11 2009
%t #+Total[Most[Rest[Divisors[#]]]]&/@Select[Range[4,200],!PrimeQ[#]&] (* _Harvey P. Dale_, Oct 28 2013 *)
%Y Cf. A027750.
%K nonn,easy
%O 1,1
%A _Juri-Stepan Gerasimov_, Aug 06 2009
%E a(4) corrected by _R. J. Mathar_, Aug 11 2009
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