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%I #7 Feb 15 2020 17:43:45
%S 30,32,33,52,60,63,90,120,150,180,210,240,270,300,330,360,390,420,450,
%T 480,510,540,570,600,630,660,690,720,750,780
%N a(1) = 30; for n >= 2, choose smallest a(n) so that no sum of 2 or more terms equals a prime.
%F a(n+1) = a(n) + 30 for n >= 7 (conjectured). - _Chai Wah Wu_, Feb 15 2020
%t (* first do *) Needs [ "Combinatorica`" ] (* then *) lst = {30}; g [ k_ ] := Block [ {j = 1, l = 2^Length@ lst}, While [ j < l && !PrimeQ [ Plus @@ NthSubset [ j, lst ] + k ], j++ ]; If [ j == l, False, True ] ]; f [ n_ ] := Block [ {k = lst [ [ -1 ] ] + 1}, While [ g@k == True, k++ ]; AppendTo [ lst, k ]; k ]; Do [ Print@ f@n, {n, 30} ]
%Y Cf. A052349, A133660, A133661.
%K nonn,more
%O 1,1
%A _Robert G. Wilson v_, Jan 01 2008
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