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Counts compositions as described by table A047969; however, only those ending with an odd part are considered.
4

%I #15 Feb 23 2015 20:29:43

%S 1,1,0,1,1,1,1,3,4,0,1,7,14,2,1,1,15,46,14,7,0,1,31,146,74,43,3,1,1,

%T 63,454,350,247,33,10,0,1,127,1394,1562,1363,273,88,4,1,1,255,4246,

%U 6734,7327,2013,724,60,13,0,1,511,12866,28394,38683,13953,5716,676,149,5,1,1

%N Counts compositions as described by table A047969; however, only those ending with an odd part are considered.

%H Alois P. Heinz, <a href="/A123685/b123685.txt">Antidiagonals n = 1..141, flattened</a>

%e Row four of table A047969 counts the 14 compositions

%e 4

%e 31 13 32 23 33

%e 211 121 112 221 212 122 222

%e 1111

%e whereas A123685 only counts

%e 31 13 32 33

%e 121 112 122

%e and 1111

%p g:= proc(b, t, l, m) option remember; `if`(t=0, b*l, add(

%p g(b, t-1, irem(k, 2), m), k=1..m-1)+g(1, t-1, irem(m, 2), m))

%p end:

%p A:= (n, k)-> g(0, k, 0, n):

%p seq(seq(A(n, d+1-n), n=1..d), d=1..13); # _Alois P. Heinz_, Nov 06 2009

%t g[b_, t_, l_, m_] := g[b, t, l, m] = If[t == 0, b*l, Sum[g[b, t-1, Mod[k, 2], m], {k, 1, m-1}] + g[1, t-1, Mod[m, 2], m]]; A[n_, k_] := g[0, k, 0, n]; Table [Table [A[n, d+1-n], {n, 1, d}], {d, 1, 13}] // Flatten (* _Jean-François Alcover_, Feb 20 2015, after _Alois P. Heinz_ *)

%Y Diagonals include A000012, A059841, A000225, A123684 and A027649.

%K nonn,tabl

%O 1,8

%A _Alford Arnold_, Oct 11 2006

%E More terms from _Alois P. Heinz_, Nov 06 2009