%I #11 Sep 08 2022 08:45:08
%S 2,1,1,1,3,3,3,3,3,3,3,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,10,10,10,
%T 10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,
%U 10,10,10,10,10,10,10,10,10,10,10,10,15,10,10,10,15,15,15,15,15,15,15
%N a(n) = floor(prime(n)/n) * ceiling(prime(n)/n) / 2.
%H G. C. Greubel, <a href="/A079415/b079415.txt">Table of n, a(n) for n = 1..10000</a>
%t fc[n_]:=Module[{c=Prime[n]/n},(Floor[c]Ceiling[c])/2]; Array[fc,80] (* _Harvey P. Dale_, May 20 2015 *)
%o (PARI) vector(80, n, floor(prime(n)/n)*ceil(prime(n)/n)/2) \\ _G. C. Greubel_, Jan 19 2019
%o (Magma) [Floor(NthPrime(n)/n)*Ceiling(NthPrime(n)/n)/2: n in [1..80]]; // _G. C. Greubel_, Jan 19 2019
%o (Sage) [floor(nth_prime(n)/n)*ceil(nth_prime(n)/n)/2 for n in (1..80)] # _G. C. Greubel_, Jan 19 2019
%Y Cf. A038605, A079416, A000040.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Jan 07 2003
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