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 A244716 Number of compositions of n with exactly 4 transitions between different parts. 2

%I

%S 1,6,31,99,278,654,1390,2714,4927,8531,13963,22134,33767,50283,72470,

%T 102891,142375,194202,260093,343973,447906,577636,735540,928009,

%U 1159312,1436145,1765079,2152787,2608321,3137866,3755214,4464420,5284570,6216275,7287298,8494233

%N Number of compositions of n with exactly 4 transitions between different parts.

%H Alois P. Heinz, <a href="/A244716/b244716.txt">Table of n, a(n) for n = 7..900</a>

%p b:= proc(n, v) option remember; `if`(n=0, [1, 0\$4],

%p add(`if`(v in [0, i], b(n-i, `if`(i<=n-i, i, -1)),

%p [0, b(n-i, `if`(i<=n-i, i, -1))[1..4][]]), i=1..n))

%p end:

%p a:= n-> b(n, 0)[5]:

%p seq(a(n), n=7..60);

%Y Column k=4 of A238279.

%K nonn

%O 7,2

%A _Joerg Arndt_ and _Alois P. Heinz_, Jul 04 2014

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Last modified March 28 11:46 EDT 2020. Contains 333083 sequences. (Running on oeis4.)