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A332955 a(0) = 1 and a(n) = A309807(n) - A309807(n-1) for n > 0.

%I A332955 #20 Mar 15 2020 16:17:21
%S A332955 1,0,0,1,1,3,3,10,11,30,48,114,166,486,727,1643,3193,7619,12489,30781,
%T A332955 52007,123418,248386,520902,909701,2349536,4417148,9055904,18451951,
%U A332955 41215779,77052793,186393151,350380117,769533521
%N A332955 a(0) = 1 and a(n) = A309807(n) - A309807(n-1) for n > 0.
%C A332955 See A309807.
%o A332955 (Ruby)
%o A332955 def A(n)
%o A332955   (1..n).to_a.permutation.select{|i| (1..n - 1).all?{|j| i[j - 1] * (j + 1) > i[j] * j}}.size
%o A332955 end
%o A332955 def A332955(n)
%o A332955   a = (0..n).map{|i| A(i)}
%o A332955   [1] + (1..n).map{|i| a[i] - a[i - 1]}
%o A332955 end
%o A332955 p A332955(10)
%Y A332955 Cf. A309807.
%K A332955 nonn
%O A332955 0,6
%A A332955 _Seiichi Manyama_, Mar 04 2020
%E A332955 a(23)-a(25) from _Giovanni Resta_, Mar 04 2020
%E A332955 a(26)-a(33) from _Bert Dobbelaere_, Mar 15 2020