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A005242
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A self-generating sequence.
(Formerly M0971)
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3
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1, 2, 4, 5, 8, 10, 12, 14, 15, 16, 19, 20, 21, 24, 25, 27, 28, 32, 33, 34, 37, 38, 40, 42, 43, 44, 46, 47, 48, 51, 53, 54, 56, 57, 58, 59, 61, 62, 63, 64, 66, 68, 69, 72, 73, 74, 77, 79, 81, 83, 84, 86, 88, 89, 91, 92, 94, 96, 97, 98, 100
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,2
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COMMENTS
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Presumably this is the lexicographically earliest sequence of distinct positive numbers with the property that sums of two or three consecutive earlier terms are excluded. - N. J. A. Sloane, Jan 07 2021
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REFERENCES
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R. K. Guy, Unsolved Problems in Number Theory, E30.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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LINKS
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PROG
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(Haskell)
import Data.List ((\\))
a005242 n = a005242_list !! (n-1)
a005242_list = f [1..] 0 0 where
f (x:xs) y z = x : f (xs \\ [x + y, x + y + z]) x y
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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