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%I #12 Mar 23 2020 15:55:43
%S 5,7,8,9,10,12,13,14,15,16,18,19,20,21,22,24,25,26,28,30,31,32,33,34,
%T 36,38,39,40,42,43,44,45,46,48,49,50,52,54,55,56,58,60,61,62,63,64,66,
%U 68,69,70,72,73,74,75,76,78,80,81,82,84,85,86,88,90,91,92
%N Numbers that are the sum of 2 different primes.
%H R. J. Mathar, <a href="/A038609/b038609.txt">Table of n, a(n) for n = 1..9225</a>
%p isA038609 := proc(n)
%p local i,p,q;
%p for i from 1 do
%p p := ithprime(i) ;
%p if 2*p > n then
%p return false;
%p fi;
%p q := n-p ;
%p if q <= p then
%p return false ;
%p end if;
%p if isprime(q) then
%p return true;
%p end if;
%p end do:
%p end proc:
%p n :=1 :
%p for c from 1 do
%p if isA038609(c) then
%p printf("%d %d\n",n,c) ;
%p n := n+1 ;
%p end if;
%p end do: # _R. J. Mathar_, Jun 09 2014
%t max = 100;
%t ip = PrimePi[max];
%t Table[Prime[i] + Prime[j], {i, ip}, {j, i + 1, ip}] // Flatten // Union // Select[#, # <= max&]& (* _Jean-François Alcover_, Mar 23 2020 *)
%Y Cf. A014091, A166081 (complement).
%K nonn
%O 1,1
%A Vasiliy Danilov (danilovv(AT)usa.net) 1998 Jul
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