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A321065
Number of ordered pairs (p,q) of permutations of [n] with equal up-down signatures and p(1)=q(1)=9.
1
23136128, 873274112, 43316046592, 2700561836672, 205352644205568, 18629724957708800, 1982309731660474368, 244043425473888612352, 34372758116984213536768, 5486719044572824902107136, 984593144718697864983347200, 197245981020715237398610116608
OFFSET
9,1
CROSSREFS
Column k=9 of A262372.
Sequence in context: A204414 A114666 A157079 * A183736 A105238 A252396
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Oct 26 2018
STATUS
approved