%I A160469
%S A160469 1,1,2,17,62,1382,21844,929569,6404582,443861162,18888466084,
%T A160469 1936767361654,58870668456604,8374643517010684,689005380505609448,
%U A160469 129848163681107301953,1736640792209901647222,418781231495293038913922
%N A160469 A 'look-a-like' of the numerators in Taylor series for tan(x)
%C A160469 This sequence makes its appearance as the first left hand column of 'triangle' 
               A160468.
%C A160469 The first difference with the sequence for the numerators in the Taylor 
               series for tan(x) A002430 occurs at a(12). Its resemblance with this 
               sequence led to the conjecture A160469(n) = A002430(n)*A089170(n-1).
%F A160469 a(n) = A002430(n)*A089170(n-1) with A002430 (n) = numer((-1)^(n-1)*2^(2*n)*(2^(2*n)-1)* 
               bernoulli(2*n)/(2*n)!) and A089170 (n-1) = numer(2*bernoulli(2*n)* 
               (4^n-1)/(2*n))/ numer((4^n-1)*bernoulli(2*n)/(2*n)!) for n = 1, 2, 
               3, .. .\
%Y A160469 Equals the first left hand column of A160468.
%Y A160469 Equals A002430(n)*A089170(n-1).
%Y A160469 Equals (A002430(n)/A036279(n))*(A117972(n)/A000265(n)).
%Y A160469 Equals A048896(n-1)*A002425(n).
%Y A160469 Cf. A156769 A 'look-a-like' of the denominators in Taylor series for 
               tan(x).
%Y A160469 Sequence in context: A125200 A071402 A002430 this_sequence A037420 A034721 
               A107815
%Y A160469 Adjacent sequences: A160466 A160467 A160468 this_sequence A160470 A160471 
               A160472
%K A160469 easy,nonn
%O A160469 1,3
%A A160469 Johannes W. Meijer (meijgia(AT)hotmail.com), May 24 2009