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%I #18 Mar 11 2016 11:59:02
%S 1,641,195709,46922017,10258694241,2176464012941,460827731023773,
%T 98540942707986273,21364658238692907265,4697818999010952011441,
%U 1046430770756355786405517,235755137688345453796236397,53640184515807269993604743389,12308974812428409561104536925709
%N Number of sequences with n copies each of 1,2,3,4 and longest increasing subsequence of length 4.
%H Alois P. Heinz, <a href="/A268840/b268840.txt">Table of n, a(n) for n = 1..400</a>
%H J. D. Horton and A. Kurn, Counting sequences with complete increasing subsequences, Congressus Numerantium, 33 (1981), 75-80. <a href="http://www.ams.org/mathscinet-getitem?mr=681905">MR 681905</a>
%H Vaclav Kotesovec, <a href="/A268840/a268840.txt">Recurrence (of order 4)</a>
%F a(n) ~ 2^(8*n-1/2) / (Pi*n)^(3/2). - _Vaclav Kotesovec_, Feb 21 2016
%Y Column k=4 of A047909.
%K nonn
%O 1,2
%A _Alois P. Heinz_, Feb 14 2016