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Triangle read by rows: coefficients of polynomials arising as traces of certain web-coloring matrices.
1

%I #22 Nov 25 2018 13:12:00

%S 1,2,2,6,8,6,24,30,42,24,120,116,216,264,120,720,532,1002,1920,1920,

%T 720,5040,2848,4626,11688,19200,15840,5040

%N Triangle read by rows: coefficients of polynomials arising as traces of certain web-coloring matrices.

%H Mark Dukes, Chris D. White, <a href="http://arxiv.org/abs/1603.01589">Web Matrices: Structural Properties and Generating Combinatorial Identities</a>, arXiv:1603.01589 [math.CO], 2016. See Fig. 7 p. 19.

%H Mark Dukes, Chris D. White, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v23i1p45">Web Matrices: Structural Properties and Generating Combinatorial Identities</a>, Electronic Journal Of Combinatorics, 23(1) (2016), #P1.45.

%e Triangle begins:

%e 1

%e 2 2

%e 6 8 6

%e 24 30 42 24

%e 120 116 216 264 120

%e 720 532 1002 1920 1920 720

%e 5040 2848 4626 11688 19200 15840 5040

%e ...

%Y Outer diagonals are A000142. Another diagonal is A121635.

%Y Cf. A281351.

%K nonn,tabl,more

%O 1,2

%A _N. J. A. Sloane_, Mar 04 2016