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A037284 Replace n with concatenation of its odd divisors >1.

%I A037284 #23 Aug 07 2024 01:16:29
%S A037284 0,0,3,0,5,3,7,0,39,5,11,3,13,7,3515,0,17,39,19,5,3721,11,23,3,525,13,
%T A037284 3927,7,29,3515,31,0,31133,17,5735,39,37,19,31339,5,41,3721,43,11,
%U A037284 3591545,23,47,3,749,525,31751
%N A037284 Replace n with concatenation of its odd divisors >1.
%H A037284 Reinhard Zumkeller, <a href="/A037284/b037284.txt">Table of n, a(n) for n = 1..10000</a>
%t A037284 Array[FromDigits[Flatten[IntegerDigits/@Rest[Select[Divisors[#], OddQ]]]]&, 60] (* _Harvey P. Dale_, Mar 03 2014 *)
%o A037284 (Haskell)
%o A037284 a037284 n
%o A037284    | a209229 n == 1 = 0
%o A037284    | otherwise      = read $ concat $ (map show) $ tail $ a182469_row n
%o A037284 -- _Reinhard Zumkeller_, May 01 2012
%o A037284 (Python)
%o A037284 from sympy import divisors
%o A037284 def a(n):
%o A037284   odd_divisors_gt1 = [d for d in divisors(n)[1:] if d%2 == 1]
%o A037284   if len(odd_divisors_gt1) == 0: return 0
%o A037284   else: return int("".join(str(d) for d in odd_divisors_gt1))
%o A037284 print([a(n) for n in range(1, 52)]) # _Michael S. Branicky_, Dec 31 2020
%Y A037284 Cf. A182469, A209229, A037277, A037283, A037285.
%K A037284 nonn,base,easy
%O A037284 1,3
%A A037284 _N. J. A. Sloane_
%E A037284 a(36) corrected by _Reinhard Zumkeller_, May 01 2012