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A037285 Replace n with concatenation of its nontrivial odd divisors.

%I A037285 #19 Dec 31 2020 09:29:03
%S A037285 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,
%T A037285 0,0,311,17,57,39,0,19,313,5,0,3721,0,11,35915,23,0,3,7,525,317,13,0,
%U A037285 3927,511,7,319,29,0,3515,0,31,37921,0,513,31133,0,17,323,5735,0,39,0
%N A037285 Replace n with concatenation of its nontrivial odd divisors.
%H A037285 Reinhard Zumkeller, <a href="/A037285/b037285.txt">Table of n, a(n) for n = 1..10000</a>
%o A037285 (Haskell)
%o A037285 import Data.List (delete)
%o A037285 a037285 n
%o A037285 | a209229 n == 1 = 0
%o A037285 | a010051 n == 1 = 0
%o A037285 | otherwise = read $ concat $ (map show) $ delete n $ tail $ a182469_row n
%o A037285 -- _Reinhard Zumkeller_, May 01 2012
%o A037285 (Python)
%o A037285 from sympy import divisors
%o A037285 def a(n):
%o A037285   nontrivial_odd_divisors = [d for d in divisors(n)[1:-1] if d%2 == 1]
%o A037285   if len(nontrivial_odd_divisors) == 0: return 0
%o A037285   else: return int("".join(str(d) for d in nontrivial_odd_divisors))
%o A037285 print([a(n) for n in range(1, 70)]) # _Michael S. Branicky_, Dec 31 2020
%Y A037285 Cf. A182469, A209229, A010051, A106708, A037283, A037284.
%K A037285 nonn,base,easy
%O A037285 1,6
%A A037285 _N. J. A. Sloane_
%E A037285 More terms from _Erich Friedman_