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A318487
Even numbers that are not the sum of two lucky-indexed lucky numbers.
2
4, 6, 10, 12, 16, 18, 20, 24, 26, 30, 34, 36, 40, 44, 46, 48, 54, 58, 60, 66, 68, 72, 74, 76, 78, 82, 86, 90, 92, 96, 100, 102, 104, 106, 110, 114, 116, 120, 122, 124, 128, 130, 134, 138, 140, 144, 146, 152, 154, 156, 158, 164, 168, 170, 176, 178, 182, 184
OFFSET
1,1
COMMENTS
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.
LINKS
EXAMPLE
28 is not in this sequence since 28 = 7 + 21 and 7 and 21 are lucky-indexed lucky numbers (A032639).
MATHEMATICA
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 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Aug 27 2018
STATUS
approved