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A244328 a(1) = a(2) = 0; for n >= 3: a(n) = floor((n*(n+1)/2) / antisigma(n)) = floor(A000217(n) / A024816(n)).

%I A244328 #22 Sep 03 2024 00:41:34
%S A244328 0,0,3,3,1,2,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
%T A244328 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
%U A244328 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1
%N A244328 a(1) = a(2) = 0; for n >= 3: a(n) = floor((n*(n+1)/2) / antisigma(n)) = floor(A000217(n) / A024816(n)).
%C A244328 Decimal expansion of 29809/900000. - _Stefano Spezia_, Sep 02 2024
%H A244328 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1).
%F A244328 a(n) = 1 for n >= 7.
%F A244328 a(n) = A244327(n) - A244329(n) for n >= 7.
%F A244328 G.f.: x^3*(3 - 2*x^2 + x^3 - x^4)/(1 - x). - _Elmo R. Oliveira_, Aug 03 2024
%F A244328 E.g.f.: exp(x) - x - 1 + x^2*(x^4 + 60*x^2 + 240*x - 360)/720. - _Stefano Spezia_, Sep 02 2024
%e A244328 For n = 10; a(10) = floor(A000217(10) / A024816(10)) = floor(55 / 37) = 1.
%t A244328 PadRight[{0, 0, 3, 3, 1, 2}, 100, 1] (* _Paolo Xausa_, Sep 01 2024 *)
%o A244328 (Magma) [Floor((n*(n+1)div 2) div ((n*(n+1)div 2)-SumOfDivisors(n))): n in [3..1000]];
%o A244328 (PARI) if(n>6,1,[0, 0, 3, 3, 1, 2][n]) \\ _Charles R Greathouse IV_, May 15 2015
%Y A244328 Cf. A000203, A000217, A024816, A244327, A244329.
%K A244328 nonn,easy
%O A244328 1,3
%A A244328 _Jaroslav Krizek_, Jul 08 2014