A109934 - OEIS

%I #10 Aug 03 2014 16:52:44

%S 4,6,27,35,51,57,65,77,87,93,95,117,119,121,123,125,135,143,145,147,

%T 155,161,171,177,185,187,189,203,205,207,209,215,217,219,221,237,245,

%U 247,249,255,261,267,275,287,289,291,297,299,301,303,305,321,323,325,327

%N Composite numbers which are not the sum of two distinct primes.

%C Perhaps there are no even terms > 6.

%H T. D. Noe, <a href="/A109934/b109934.txt">Table of n, a(n) for n = 1..10000</a>

%t f[n_] := (p = 0; pn = PrimePi[n];

%t Do[ If[n == Prime[i] + Prime[k], p = p + 1; If[p > 2, Break[]]], {i, 1, pn},

%t {k, i+1, pn}]; p );

%t Select[Range[2, 400], ! PrimeQ[#] && f[#] == 0 & ] (* _Jean-François Alcover_, Mar 07 2011 *)

%Y Cf. A025583.

%K nonn

%O 1,1

%A _Amarnath Murthy_, Jul 19 2005