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Triangle T(n,k) giving number of fixed 5 X k polyominoes with n cells (n >= 5, 1<=k<=n-4).
4

%I #12 Oct 02 2017 21:31:25

%S 1,0,16,0,38,83,0,32,376,230,0,10,784,1526,497,0,1,987,5154,4180,932,

%T 0,0,778,11328,18944,9458,1591,0,0,370,17598,58665,52488,18936,2538,0,

%U 0,101,19912,135325,204466,123652,34726,3845,0,0,15,16440,241550,611859

%N Triangle T(n,k) giving number of fixed 5 X k polyominoes with n cells (n >= 5, 1<=k<=n-4).

%H Andrew Howroyd, <a href="/A059681/b059681.txt">Table of n, a(n) for n = 5..1279</a>

%H R. C. Read, <a href="http://cms.math.ca/cjm/v14/cjm1962v14.0001-0020.pdf">Contributions to the cell growth problem</a>, Canad. J. Math., 14 (1962), 1-20.

%F T(n,k) = 0 for n > 5*k. - _Andrew Howroyd_, Oct 02 2017

%e Triangle starts:

%e 1;

%e 0, 16;

%e 0, 38, 83;

%e 0, 32, 376, 230;

%e 0, 10, 784, 1526, 497;

%e 0, 1, 987, 5154, 4180, 932;

%e 0, 0, 778, 11328, 18944, 9458, 1591;

%e ...

%Y Column sums are row 5 of A292357.

%Y Cf. A059678, A059679, A059680.

%K nonn,easy,nice,tabl

%O 5,3

%A _N. J. A. Sloane_, Feb 05 2001

%E a(24) corrected and terms a(26) and beyond from _Andrew Howroyd_, Oct 02 2017