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%I #23 Mar 18 2024 12:05:08
%S 5,16,24,36,48,60,78,84,90,114,144,120,168,180,234,246,288,240,210,
%T 324,300,360,474,330,528,576,390,462,480,420,570,510,672,792,756,876,
%U 714,798,690,1038,630,1008,930,780,960,870,924,900,1134,1434,840,990,1302,1080,1230,1518
%N Least number expressible as a sum of two distinct primes in exactly n ways.
%H Paolo P. Lava, <a href="/A087747/b087747.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = min({m >= 1 : A117929(m) = n}). - _Peter Munn_, May 01 2023
%e a(2)=16 because we have 16=3+13=5+11, followed by 18=5+13=7+11; 20=3+17=7+13; 22=3+19=5+17; 26=3+23=7+19;...
%t Module[{nn=2000,ip},ip=Table[{n,Length[Select[IntegerPartitions[n,{2}], #[[1]]!=#[[2]]&&AllTrue[#,PrimeQ]&]]},{n,nn}];Table[SelectFirst[ip, #[[2]]==k&],{k,60}]][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jul 11 2020 *)
%Y Cf. A117929.
%K nonn
%O 1,1
%A _Lekraj Beedassy_, Oct 02 2003
%E More terms from John Dethridge (jcd(AT)ms.unimelb.edu.au), Jan 08 2004
%E More terms from _Hugo Pfoertner_, Sep 23 2004
%E Reinserted a(18), a(19) and a(20) by _Paolo P. Lava_, May 26 2014