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A060408 Triangle T(n,k) in which n-th row gives numbers of super edge-magic labelings of (n,k)-graphs, for n >= 2, and 1 <= k <= 2n-3. 2

%I

%S 1,3,2,1,6,6,6,4,2,10,14,20,24,24,16,8,15,26,48,80,120,144,144,96,48,

%T 21,44,99,212,420,720,1080,1296,1296,864,432,28,68,180,464,1140,2520,

%U 5040,8640,12960,15552,15552,10368,5184

%N Triangle T(n,k) in which n-th row gives numbers of super edge-magic labelings of (n,k)-graphs, for n >= 2, and 1 <= k <= 2n-3.

%C (n,k)-graphs are simple graphs with n vertices and k edges.

%C Row indexed n has length 2n-3.

%C The diagonal counting the super edge-magic labelings of (n,n)-graphs appears to be A077613(n-1).

%H Jason Kimberley, <a href="/A060408/b060408.txt">Rows n = 2..101 of triangle</a>

%H R. M. Figueroa-Centeno et al., <a href="http://dx.doi.org/10.1016/S0012-365X(00)00314-9">The place of super edge-magic labelings among other classes of labelings</a>, Discrete Math., 231 (2001), 153-168.

%e 1; 3,2,1; 6,6,6,4,2; 10,14,20,24,24,16,8; ...

%o (MAGMA) A060408 := func< n, k | &+[ Integers() | &*[ Integers() | a[j] : j in [i .. i+k-1] ] : i in [3 .. 2*n-k] ] where a is [ j lt 3 select 0 else j le n+1 select (j-1) div 2 else (2*n-j+1) div 2 : j in [1..2*n-1] ] >; [[ A060408(n,k): k in [1..2*n-3] ]: n in [1..10]];

%K nonn,tabf,easy

%O 2,2

%A _N. J. A. Sloane_, Apr 06 2001

%E Entry T(3,3)=1 (that was erroneously missing from the table of Figueroa-Centeno et al. making the rows appear to be irregular) inserted by, DOI reference provided by, and empirical cross reference for the T(n,n) diagonal observed by _Jason Kimberley_, Apr 16 2010

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Last modified May 18 00:43 EDT 2021. Contains 343992 sequences. (Running on oeis4.)