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%I #24 Sep 08 2022 08:45:48
%S 0,5,21,45,117,165,285,357,525,837,957,1365,1677,1845,2205,2805,3477,
%T 3717,4485,5037,5325,6237,6885,7917,9405,10197,10605,11445,11877,
%U 12765,16125,17157,18765,19317,22197,22797,24645,26565,27885,29925,32037
%N a(n) = prime(n)^2-4.
%C Least common multiple of prime(n)-2 and prime(n)+2.
%H G. C. Greubel, <a href="/A166010/b166010.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A001248(n)-4 = A040976(n)*A052147(n). [_Bruno Berselli_, Apr 17 2012]
%t f[n_]:=LCM[n-2,n+2]; lst={};Do[p=Prime[n];AppendTo[lst,f[p]],{n,5!}]; lst
%t Prime[Range[5!]]^2 - 4 (* _Zak Seidov_, Apr 17 2012 *)
%o (Magma) [NthPrime(n)^2-4: n in [1..41]]; // _Bruno Berselli_, Apr 17 2012
%o (PARI) a(n)=prime(n)^2-4 \\ _Charles R Greathouse IV_, Apr 17 2012
%Y Cf. A066830, A084921, A166011.
%Y Cf. A049001, A084920, A182200; A182174.
%K nonn,easy
%O 1,2
%A _Vladimir Joseph Stephan Orlovsky_, Oct 04 2009
%E Definition rewritten by _Bruno Berselli_, Apr 17 2012
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