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%I #12 Nov 28 2016 03:58:04
%S 2,3,2,3,2,4,2,4,3,4,2,6,2,4,4,5,2,6,2,6,4,4,2,8,3,4,4,6,2,8,2,6,4,4,
%T 4,9,2,4,4,8,2,8,2,6,6,4,2,10,3,6,4,6,2,8,4,8,4,4,2,12,2,4,6,7,4,8,2,
%U 6,4,8,2,12,2,4,6,6,4,8,2,10,5,4,2,12,4,4,4,8,2,12,4,6,4,4,4,12,2,6,6
%N a(1) = 2; for n>1: a(n) = integer part of y-value when x=0 in (y-tau(n))/(x-1)=(1-tau(n))/(n-1), tau=A000005.
%C a(n) = 2 iff n is prime.
%H G. C. Greubel, <a href="/A096737/b096737.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = floor((n*tau(n)-1)/(n-1))for n>1, a(1) = 2.
%F a(1)=2, a(2)=3, a(n)=tau(n) if n>2. - _Michael Somos_, Sep 03 2006
%e See A096736.
%t Join[{2, 3}, Table[Floor[(n*DivisorSigma[0, n] - 1)/(n - 1)], {n,3,100}]] (* _G. C. Greubel_, Nov 27 2016 *)
%Y Cf. A096736.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Jul 06 2004