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%I #9 Jun 20 2014 07:13:57
%S 3,5,7,13,19,23,31,43,53,61,73,89,103,113,131,151,167,181,199,229,251,
%T 271,293,317,349,373,401,433,463,491,523,557,593,619,661,701,739,773,
%U 811,859,887,941,983,1033,1069,1123,1171,1223,1259,1321,1373,1429,1483
%N Largest prime <= n * (n + 1) / 2.
%H Harry J. Smith, <a href="/A065384/b065384.txt">Table of n, a(n) for n = 2..1000</a>
%t PrimePrev[n_]:=Module[{k=n},While[ !PrimeQ[k],k-- ];k];f[n_]:=n*(n+1)/2;lst={};Do[AppendTo[lst,PrimePrev[f[n]]],{n,6!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Feb 26 2010 *)
%o (PARI) { for (n=2, 1000, write("b065384.txt", n, " ", precprime(n*(n + 1)/2)) ) } [_Harry J. Smith_, Oct 17 2009]
%Y Cf. A065382, A053001, A064383, A000217.
%K nonn
%O 2,1
%A _Reinhard Zumkeller_, Nov 05 2001
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