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A109885 Let n be an even integer > 2. Let PrimeP be the number of prime partition pairs {p,q} corresponding to n such that n = p + q, p and q are prime and p <= q. Let CompP be the number of composite partition pairs {r,s} corresponding to n such that n = r + s, r is prime, s is composite and r <= s. For what n's is 2*PrimeP > CompP? 1

%I #7 Mar 21 2015 04:55:29

%S 4,10,22,24,34,36,48,54,60,66,72,78,84,90,102,114,120,126,144,150,156,

%T 168,180,186,198,204,210,240,246,252,270,294,300,324,330,360,378,390,

%U 420,450,462,480,510,540,546,570,600,630,660,690,714,720,750,780,840

%N Let n be an even integer > 2. Let PrimeP be the number of prime partition pairs {p,q} corresponding to n such that n = p + q, p and q are prime and p <= q. Let CompP be the number of composite partition pairs {r,s} corresponding to n such that n = r + s, r is prime, s is composite and r <= s. For what n's is 2*PrimeP > CompP?

%C Except for a(1), a(2) a(3) & a(5), a(n)==0 (mod 6). - _Robert G. Wilson v_

%t fQ[n_] := Block[{t = n - Prime@Range@PrimePi[n/2]}, 2Length[Select[t, PrimeQ]] > Length[t]]; Select[ 2Range[2, 434], fQ[ # ] &] (* _Robert G. Wilson v_, Nov 03 2005 *)

%K nonn

%O 1,1

%A Gilmar Rodriguez Pierluissi (gilmarlily(AT)yahoo.com), Aug 31 2005

%E Edited by _Robert G. Wilson v_, Nov 03 2005

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Last modified May 10 08:52 EDT 2024. Contains 372373 sequences. (Running on oeis4.)