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%I #14 Sep 14 2019 14:58:19
%S 4,6,10,12,16,18,20,24,26,30,34,36,40,44,46,48,54,58,60,66,68,72,74,
%T 76,78,82,86,90,92,96,100,102,104,106,110,114,116,120,122,124,128,130,
%U 134,138,140,144,146,152,154,156,158,164,168,170,176,178,182,184
%N Even numbers that are not the sum of two lucky-indexed lucky numbers.
%C Conjecture (checked up to 10^7): every even number larger than 199254 is the sum of two lucky-indexed lucky numbers, so this sequence is finite with 1714 terms.
%H Amiram Eldar, <a href="/A318487/b318487.txt">Table of n, a(n) for n = 1..1714</a>
%e 28 is not in this sequence since 28 = 7 + 21 and 7 and 21 are lucky-indexed lucky numbers (A032639).
%t L = Table[2*i + 1, {i, 0, 150000}]; For[n = 2, n < Length[L], r = L[[n++]]; L = ReplacePart[L, Table[r*i -> Nothing, {i, 1, Length[L]/r}]]]; a = L[[Select[L, # <= Length[L] &]]]; v = Select[Range[2, 300000, 2], IntegerPartitions[#, {2}, a] == {} &]; (* after _Jean-François Alcover_ at A000959 and _Giovanni Resta_ at A303403 *)
%Y Cf. A000959, A032639, A303403.
%K nonn
%O 1,1
%A _Amiram Eldar_, Aug 27 2018
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