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Irregular triangle read by rows: T(n,k) is the number of polyhedra with n faces and k vertices (n >= 4, k=4..2n-4).
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%I #26 Mar 27 2021 22:49:40

%S 1,0,1,1,0,1,2,2,2,0,0,2,8,11,8,5,0,0,2,11,42,74,76,38,14,0,0,0,8,74,

%T 296,633,768,558,219,50,0,0,0,5,76,633,2635,6134,8822,7916,4442,1404,

%U 233,0,0,0,0,38,768,6134,25626,64439,104213,112082,79773,36528,9714,1249

%N Irregular triangle read by rows: T(n,k) is the number of polyhedra with n faces and k vertices (n >= 4, k=4..2n-4).

%C Because of duality, T(n,k) = T(k,n). - _Ivan Neretin_, May 25 2016

%C The number of edges is n+k-2. - _Andrew Howroyd_, Mar 27 2021

%H Andrew Howroyd, <a href="/A212438/b212438.txt">Table of n, a(n) for n = 4..199</a> (rows 4..17)

%H Gunnar Brinkmann and Brendan McKay, <a href="https://users.cecs.anu.edu.au/~bdm/papers/plantri-full.pdf">Fast generation of planar graphs (expanded edition)</a>, Table 9-11.

%H G. P. Michon, <a href="http://www.numericana.com/data/polyhedra.htm">Counting Polyhedra</a>

%e Triangle begins:

%e 1

%e 0 1 1

%e 0 1 2 2 2

%e 0 0 2 8 11 8 5

%e 0 0 2 11 42 74 76 38 14

%e 0 0 0 8 74 296 633 768 558 219 50

%e 0 0 0 5 76 633 2635 6134 8822 7916 4442 1404 233

%e ...

%Y A049337, A058787, A212438 are all versions of the same triangle.

%Y Row sums (the same as column sums) are A000944.

%Y Main diagonal is A002856.

%Y Cf. A002840 (by edges), A239893.

%K nonn,tabf

%O 4,7

%A _N. J. A. Sloane_, May 16 2012

%E Terms a(53) and beyond from _Andrew Howroyd_, Mar 27 2021