OFFSET
1,2
FORMULA
a(n) = Sum_{k=1..n} k * A245667(n,k). - Alois P. Heinz, Nov 02 2018
EXAMPLE
For n = 2 there are 4 such sequences: (1,1), (1,2), (2,1), and (2,2).
The corresponding lengths of longest (strictly) increasing subsequences of these is 1, 2, 1, 1, so a(2) = 5.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Jeffrey Shallit, Aug 02 2016
EXTENSIONS
a(8)-a(18) from Alois P. Heinz, Nov 02 2018
STATUS
approved