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A244327 a(n) = floor((n*(n+1)/2) / sigma(n)) = floor(A000217(n) / A000203(n)).

%I A244327 #16 Sep 17 2024 15:45:29
%S A244327 1,1,1,1,2,1,3,2,3,3,5,2,6,4,5,4,8,4,9,5,7,7,11,5,10,8,9,7,14,6,15,8,
%T A244327 11,11,13,7,18,12,13,9,20,9,21,11,13,15,23,9,21,13,18,14,26,12,21,13,
%U A244327 20,19,29,10,30,20,19,16,25,15,33,18,25,17,35,13,36
%N A244327 a(n) = floor((n*(n+1)/2) / sigma(n)) = floor(A000217(n) / A000203(n)).
%C A244327 RECORD transform of a(n) is A140475 (union of number 1 and primes >= 5).
%C A244327 Sequence of numbers n such that a(n) = a(n+1) = A244666.
%H A244327 Alois P. Heinz, <a href="/A244327/b244327.txt">Table of n, a(n) for n = 1..20000</a>
%F A244327 a(n) = A244328(n) + A244329(n) for n >= 7.
%e A244327 For n = 10; a(10) = floor(A000217(10) / A000203(10)) = floor(55 / 18) = 3.
%p A244327 a:= n-> floor(n*(n+1)/(2*numtheory[sigma](n))):
%p A244327 seq(a(n), n=1..100);  # _Alois P. Heinz_, Mar 28 2018
%t A244327 A244327[n_] := Floor[n*(n + 1)/(2*DivisorSigma[1, n])];
%t A244327 Array[A244327, 100] (* _Paolo Xausa_, Sep 01 2024 *)
%o A244327 (Magma) [Floor((n*(n+1)div 2) div (SumOfDivisors(n))): n in [1..1000]];
%Y A244327 Cf. A000203, A000217, A024816, A244328, A244329, A244666.
%K A244327 nonn
%O A244327 1,5
%A A244327 _Jaroslav Krizek_, Jul 08 2014