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%I #14 Aug 02 2024 03:17:19
%S 1,0,1,1,13,12,324,1352,18368,19152,1994322,8810748,193690826,
%T 829046868,34563283272,274895151856,14554448767872,8178592487376,
%U 2493850026398472,33842416675133248,1037660717168380800,6072370562498569056,682597834324732589120,5390950170768906240000
%N Sum of odd divisors of !n.
%C !n is a subfactorial number (A000166).
%C Property of the sequence: for n > 4 the sum of odd divisors of !n seems even.
%H Amiram Eldar, <a href="/A195210/b195210.txt">Table of n, a(n) for n = 0..81</a>
%F a(n) = A000593(A000166(n)), for n != 1. - _Amiram Eldar_, Aug 02 2024
%e a(7) = 1352 because the divisors of !7 = 1854 are {1, 2, 3, 6, 9, 18, 103, 206, 309, 618, 927, 1854}, and the sum of the 6 odd divisors 1, 3, 9, 103, 309 and 927 is 1352.
%t Table[Total[Select[Divisors[Subfactorial[n]], OddQ[ # ]&]], {n, 0, 21}]
%Y Cf. A000166, A000593, A195207, A195208, A195209.
%K nonn
%O 0,5
%A _Michel Lagneau_, Sep 13 2011
%E a(22)-a(23) from _Amiram Eldar_, Aug 02 2024