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Sums of lengths of longest (not necessarily strictly) increasing subsequences of all n^n length-n lists of integers from {1,2,...,n}.
1

%I #14 Nov 03 2018 17:08:12

%S 1,7,63,716,10050,167707,3246985,71601112,1772086842,48644809445,

%T 1466863148619,48202848917302,1714563272612502

%N Sums of lengths of longest (not necessarily strictly) increasing subsequences of all n^n length-n lists of integers from {1,2,...,n}.

%e For n = 2 there are 4 such sequences: (1,1), (1,2), (2,1), and (2,2).

%e The corresponding lengths of longest (not necessarily strictly) increasing subsequences of these is 2, 2, 1, 2, so a(2) =7.

%Y Cf. A003316, which computes the same thing for permutations.

%Y Cf. A275576, which computes the same thing for strictly increasing subsequences.

%K nonn,more

%O 1,2

%A _Jeffrey Shallit_, Aug 02 2016

%E a(8)-a(13) from _Alois P. Heinz_, Nov 02 2018