A321065 - OEIS

%I #4 Oct 27 2018 14:27:04

%S 23136128,873274112,43316046592,2700561836672,205352644205568,

%T 18629724957708800,1982309731660474368,244043425473888612352,

%U 34372758116984213536768,5486719044572824902107136,984593144718697864983347200,197245981020715237398610116608

%N Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=9.

%Y Column k=9 of A262372.

%K nonn

%O 9,1

%A _Alois P. Heinz_, Oct 26 2018