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A058208 Floor(6*n*sqrt(n)/Pi^2) - sigma(n), where sigma(n) is the sum of the divisors of n (A000203). 4

%I

%S -1,-2,-1,-3,0,-4,3,-2,3,1,10,-3,14,7,11,7,24,7,30,12,26,26,43,11,44,

%T 38,45,34,64,27,72,47,67,66,77,40,98,82,92,63,117,69,127,93,105,117,

%U 147,78,151,121,149,129,180,121,175,134,181,178,215,114,227,200

%N Floor(6*n*sqrt(n)/Pi^2) - sigma(n), where sigma(n) is the sum of the divisors of n (A000203).

%C Always > 0 for n > 12.

%D D. S. Mitrinovic et al., Handbook of Number Theory, Kluwer, Section III.1.1.b.

%o (PARI) a(n)=6*n*sqrt(n)\Pi^2 - sigma(n) \\ _Charles R Greathouse IV_, Feb 14 2013

%Y Cf. A000203, A057641, A055682.

%K sign

%O 1,2

%A _N. J. A. Sloane_, Nov 29 2000

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Last modified March 23 14:17 EDT 2019. Contains 321431 sequences. (Running on oeis4.)