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Number of odd divisors of Bell(n).
3

%I #13 Nov 23 2019 04:05:30

%S 1,1,1,2,4,2,4,2,12,16,6,8,8,2,4,8,4,10,8,12,12,16,64,8,8,64,16,64,16,

%T 16,64,4,8,4,16,48,16,8,8,8,8,16,2,128,16,32,16,64,16,4,16,8,24,16,8,

%U 2,576,8,8,16,8,128,4,128,16,8,64,8,8,16,16

%N Number of odd divisors of Bell(n).

%H Amiram Eldar, <a href="/A280638/b280638.txt">Table of n, a(n) for n = 0..104</a>

%F a(n) = A001227(A000110(n)).

%t Table[B=BellB[n]; r=IntegerExponent[B, 2]; DivisorSigma[0, B/2^r], {n, 0, 60}]

%Y Cf. A000110, A001227, A280589.

%K nonn

%O 0,4

%A _Vincenzo Librandi_, Jan 07 2017

%E Offset corrected by _Amiram Eldar_, Nov 23 2019