Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #12 Mar 09 2018 03:37:33
%S 1,20,507,19552,1113485,88725876,9452410135,1299140690912,
%T 223938108997497,47323772172058420,12033854264863090451,
%U 3625294706255832787200,1276951433895343148472517
%N Total length of strings on n symbols in Stockhausen problem.
%H R. C. Read, <a href="http://dx.doi.org/10.1016/S0012-365X(96)00255-5">Combinatorial problems in theory of music</a>, Discrete Math. 167 (1997), 543-551.
%H Ronald C. Read, Lily Yen, <a href="https://doi.org/10.1006/jcta.1996.0085">A note on the Stockhausen problem</a>, J. Comb. Theory, Ser. A 76, No. 1 (1996), 1-10.
%F a(n) = n * Sum_{k=0..n-1} binomial(n - 1, k) * (2*k+1) * (2*k+1)! / 2^k. - _Sean A. Irvine_, Mar 08 2018
%K nonn
%O 1,2
%A _Lily Yen_