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A225496
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Numbers having no balanced prime factors, cf. A006562.
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6
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1, 2, 3, 4, 6, 7, 8, 9, 11, 12, 13, 14, 16, 17, 18, 19, 21, 22, 23, 24, 26, 27, 28, 29, 31, 32, 33, 34, 36, 37, 38, 39, 41, 42, 43, 44, 46, 47, 48, 49, 51, 52, 54, 56, 57, 58, 59, 61, 62, 63, 64, 66, 67, 68, 69, 71, 72, 73, 74, 76, 77, 78, 79, 81, 82, 83, 84
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listen;
history;
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internal format)
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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PROG
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(Haskell)
import Data.Set (singleton, fromList, union, deleteFindMin)
a225496 n = a225496_list !! (n-1)
a225496_list = 1 : h (singleton p) ps [p] where
(p:ps) = a178943_list
h s xs'@(x:xs) ys
| m > x = h (s `union` (fromList $ map (* x) (1 : ys))) xs ys
| otherwise = m : h (s' `union` (fromList $ map (* m) ys')) xs' ys'
where ys' = m : ys; (m, s') = deleteFindMin s
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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