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Number of multisets of nonempty words with a total of n letters over binary alphabet containing the second letter such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.
2

%I #5 Oct 16 2017 11:26:51

%S 1,3,10,24,62,140,329,725,1631,3548,7820,16887,36767,79046,170799,

%T 365883,786361,1679486,3594580,7656839,16331933,34705064,73810524,

%U 156501393,332001987,702530049,1486995062,3140712201,6634309660,13988510961,29494808402,62091823865

%N Number of multisets of nonempty words with a total of n letters over binary alphabet containing the second letter such that within each prefix of a word every letter of the alphabet is at least as frequent as the subsequent alphabet letter.

%H Alois P. Heinz, <a href="/A293797/b293797.txt">Table of n, a(n) for n = 2..1000</a>

%F a(n) = A293732(n) - A000041(n).

%Y Column k=2 of A293109.

%Y Cf. A000041, A293732.

%K nonn

%O 2,2

%A _Alois P. Heinz_, Oct 16 2017