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A077477
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Least positive integers not excluded by the rule that if n is present then 2n+1 and 3n+1 are not allowed.
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2
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1, 2, 6, 8, 9, 10, 11, 12, 14, 15, 16, 18, 20, 22, 24, 26, 27, 30, 32, 35, 36, 38, 39, 40, 42, 44, 47, 48, 50, 51, 52, 54, 56, 57, 58, 59, 60, 62, 63, 64, 66, 68, 69, 70, 72, 74, 75, 76, 78, 80, 83, 84, 86, 87, 88, 90, 92, 93, 94, 96
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Reinhard Zumkeller, Table of n, a(n) for n - 1..1000
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FORMULA
| What is the limit of a(n)/n?
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EXAMPLE
| a(5)=9 since 9 is not equal to 2*a(k)+1 nor 3*a(k)+1 for 1<=k<5; and since 9 is allowed to be present, then 19(=2*9+1) and 28(=3*9+1) are to be excluded.
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PROG
| (Haskell)
import Data.List (delete)
a077477 n = a077477_list !! (n-1)
a077477_list = f [1..] where
f (x:xs) = x : f (delete (2*x + 1) $ delete (3*x + 1) xs)
-- Reinhard Zumkeller, Sep 14 2011
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CROSSREFS
| Cf. A002977.
Sequence in context: A064165 A003610 A201776 * A095879 A120736 A130099
Adjacent sequences: A077474 A077475 A077476 * A077478 A077479 A077480
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KEYWORD
| easy,nice,nonn
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AUTHOR
| Paul D. Hanna (pauldhanna(AT)juno.com), Nov 08 2002
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