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Number of collections of nonempty multisets with a total of n objects of exactly two colors.
3

%I #9 Feb 08 2020 07:01:18

%S 2,8,23,56,127,268,547,1072,2055,3836,7045,12692,22566,39542,68520,

%T 117354,199082,334446,557175,920528,1509606,2457698,3974813,6387026,

%U 10201990,16201424,25589505,40205766,62857564,97800674,151475564,233575222,358656011,548476318

%N Number of collections of nonempty multisets with a total of n objects of exactly two colors.

%H Vaclav Kotesovec, <a href="/A255942/b255942.txt">Table of n, a(n) for n = 2..10000</a> (terms 2..1000 from Alois P. Heinz)

%F a(n) = A255903(n,2).

%Y Column k=2 of A255903.

%K nonn

%O 2,1

%A _Alois P. Heinz_, Mar 11 2015