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%I #37 Oct 14 2025 21:28:13
%S 0,1,1,2,5,7,26,33,158,191,1113,1304,8937,10241,80624,90865,807544,
%T 898409,8893225,9791634,106809565,116601199,1389422754,1506023953,
%U 19461710190,20967734143,292042254049,313009988192,4674182088737
%N a(0) = 0, a(1) = 1, a(2*n) = n*a(2*n-1) + a(2*n-2), a(2*n+1) = a(2*n) + a(2*n-1).
%C Conjecture: for n >= 1, a(n-1) is not divisible by n, except at n=5 (verified for n <= 10^7). - _Davide Oliveri_, Oct 03 2025
%H Seiichi Manyama, <a href="/A056921/b056921.txt">Table of n, a(n) for n = 0..897</a>
%F Numerators of continued fraction for alternating factorial.
%Y Cf. A058797, A361938.
%K frac,easy,nonn
%O 0,4
%A _Aleksandar Petojevic_, Sep 05 2000
%E More terms from _James Sellers_, Sep 07 2000