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A103880 Square array T(n,k) read by antidiagonals: denominators of Stirling numbers of first kind with negative argument S1(-n,k), n,k>=0.

%I A103880 #5 Apr 30 2014 01:31:16
%S A103880 1,1,1,2,1,1,6,4,1,1,24,36,8,1,1,120,288,216,16,1,1,720,7200,3456,
%T A103880 1296,32,1,1,5040,14400,432000,41472,7776,64,1,1,40320,235200,2592000,
%U A103880 25920000,497664,46656,128,1,1,362880,11289600,889056000,51840000
%N A103880 Square array T(n,k) read by antidiagonals: denominators of Stirling numbers of first kind with negative argument S1(-n,k), n,k>=0.
%H A103880 D. Loeb, <a href="http://arXiv.org/abs/math.CO/9502217">Generalization of the Stirling numbers of first kind</a>
%F A103880 T(n, k) = (-1)^(k+1) * Sum[i=1..n, C(n, i)*(-1)^i*i^(-k) ].
%F A103880 G.f. of n-th row: 1/n! * 1/Prod[i=1..n, 1+x/i ].
%e A103880 1, 0, 0, 0, 0, 0,
%e A103880 1, -1, 1, -1, 1, -1,
%e A103880 1/2, -3/4, 7/8, -15/16, 31/32, -63/64,
%e A103880 1/6, -11/36, 85/216, -575/1296, 3661/7776, -22631/46656,
%e A103880 1/24,-25/288,415/3456,-5845/41472,76111/497664,-952525/5971968,
%o A103880 (PARI) T(n,k)=denominator(1/n!*polcoeff(Ser(1/prod(i=1,n,1+x/i)),k))
%Y A103880 Numerators are in A103879. Cf. A008969.
%K A103880 nonn,tabl,frac
%O A103880 0,4
%A A103880 _Ralf Stephan_, Feb 20 2005