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A037285
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Replace n with concatenation of its nontrivial odd divisors.
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5
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0, 0, 0, 0, 0, 3, 0, 0, 3, 5, 0, 3, 0, 7, 35, 0, 0, 39, 0, 5, 37, 11, 0, 3, 5, 13, 39, 7, 0, 3515, 0, 0, 311, 17, 57, 39, 0, 19, 313, 5, 0, 3721, 0, 11, 35915, 23, 0, 3, 7, 525, 317, 13, 0, 3927, 511, 7, 319, 29, 0, 3515, 0, 31, 37921, 0, 513, 31133, 0, 17, 323, 5735, 0, 39, 0
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OFFSET
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1,6
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LINKS
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PROG
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(Haskell)
import Data.List (delete)
a037285 n
| a209229 n == 1 = 0
| a010051 n == 1 = 0
| otherwise = read $ concat $ (map show) $ delete n $ tail $ a182469_row n
(Python)
from sympy import divisors
def a(n):
nontrivial_odd_divisors = [d for d in divisors(n)[1:-1] if d%2 == 1]
if len(nontrivial_odd_divisors) == 0: return 0
else: return int("".join(str(d) for d in nontrivial_odd_divisors))
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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