%I A064190
%S A064190 1,2,6,16,48,72,272,816,1440,1440,7936,23808,44352,57600,43200,353792,
%T A064190 1061376,2027520,2903040,3024000,1814400,22368256,67104768,129964032,
%U A064190 195379200,232243200,203212800,101606400,1903757312,5711271936
%N A064190 Triangle T(n,k) generalizing the tangent numbers.
%H A064190 J. L. Arregui, <a href="http://arXiv.org/abs/math.NT/0109108">Tangent 
               and Bernoulli numbers</a> related to Motzkin and Catalan numbers 
               by means of numerical triangles.
%F A064190 T(n+1, m) = m*(m+1)*Sum_{k = m-1, n} T(n, k)
%e A064190 1; 2,6; 16,48,72; 272,816,1440,1440; ...
%Y A064190 First column gives A000182.
%Y A064190 If m*(m+1) is replaced in the formula by m*m, the first column is the 
               sequence of secant numbers A000364. - Jose L. Arregui (arregui(AT)posta.unizar.es), 
               Oct 09 2001
%Y A064190 Sequence in context: A071726 A148443 A148444 this_sequence A151281 A045694 
               A129772
%Y A064190 Adjacent sequences: A064187 A064188 A064189 this_sequence A064191 A064192 
               A064193
%K A064190 nonn,tabl,easy,nice
%O A064190 0,2
%A A064190 N. J. A. Sloane (njas(AT)research.att.com), Sep 21 2001
%E A064190 More terms from Vladeta Jovovic (vladeta(AT)eunet.rs), Sep 22 2001