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%I #15 Oct 27 2012 23:06:03
%S 1,0,2,2,4,2,5,2,8,7,7,2,10,2,9,10,16,2,16,2,16,11,13,2,20,15,13,22,
%T 20,2,13,2,32,14,11,20,32,2,18,18,33,2,33,2,26,31,20,2,44,28,34,20,31,
%U 2,47,23,38,19,18,2,42,2,15,37,64,29,37,2,33,22,43,2,58,2,26,57,40,42
%N Number of k for which n does not divide Stirling_2 subset numbers S(n, k).
%H Vincenzo Librandi, <a href="/A005128/b005128.txt">Table of n, a(n) for n = 0..10000</a>
%t Prepend[ Array[ Length[ Select[ Table[ StirlingS2[ #, k ]/#, {k, 0, #} ], !IntegerQ[ # ]& ] ]&, 100 ], 1 ]
%Y Cf. A048993.
%K nonn
%O 0,3
%A _Olivier Gérard_