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%I #15 May 10 2019 21:42:34
%S 2,2,2,2,6,2,2,12,6,2,2,20,24,6,2,2,30,72,24,6,2,2,42,172,120,24,6,2,
%T 2,56,352,480,120,24,6,2,2,72,646,1512,720,120,24,6,2,2,90,1094,3976,
%U 3600,720,120,24,6,2,2,110,1742,9144,14184,5040,720,120,24,6,2,2,132,2642,18990,45992,30240,5040,720,120
%N Square array in A071223 read by antidiagonals.
%H T. M. Cover, <a href="http://www.jstor.org/stable/2946294">The number of linearly inducible orderings of points in d-space</a>, SIAM J. Applied Math., 15 (1967), 434-439.
%F See A071223, which is the main entry for this array.
%e Array begins
%e 2 2 2 2 2 ...
%e 2 6 6 6 6 ...
%e 2 12 24 24 24 ...
%e 2 20 72 120 120 ...
%e 2 30 172 480 720 ...
%e ...
%p A071223 := proc(n,k)
%p if k=1 and n>=2 then
%p 2
%p elif n=2 and k>=1 then
%p 2
%p elif k>=n-1 then
%p n!
%p else
%p procname(n-1, k)+(n-1)*procname(n-1, k-1)
%p fi ;
%p end proc:
%p for d from 3 to 16 do
%p for k from 1 to d-2 do
%p n := d-k ;
%p printf("%d,",A071223(n,k)) ;
%p end do:
%p end do; # _R. J. Mathar_, Oct 31 2011
%Y Cf. A071223.
%K nonn,tabl
%O 2,1
%A _N. J. A. Sloane_, Oct 30 2011
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