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%I #12 Sep 18 2018 04:46:31
%S 1,1,8,72,800,9754,121130,1508919,18787340,233941432,2912502538,
%T 36262251784,451462592746,5620827261214,69979671635586,
%U 871259379376415,10847277968319460,135050246142276024,1681392997487494568,20933580943579610208,260625895660539796224
%N Number of edge-disjoint paths between opposite corners of 3 X n grid.
%D rec.puzzles Dec 10 1995.
%H Sean A. Irvine, <a href="/A013992/b013992.txt">Table of n, a(n) for n = 0..100</a>
%H Sean A. Irvine, <a href="/A013992/a013992.pdf">Note on A013992</a>
%F G.f.: (49*x^16 + 49*x^15 - 745*x^14 - 990*x^13 + 4108*x^12 + 10320*x^11 - 994*x^10 - 12122*x^9 + 2071*x^8 + 433*x^7 + 6952*x^6 - 7424*x^5 + 3184*x^4 - 583*x^3 - 5*x^2 + 15*x - 1) / ((7*x^8 - 19*x^7 - 22*x^6 + 98*x^5 + 39*x^4 + 38*x^3 - 60*x^2 + 17*x - 1) * (7*x^8 + 33*x^7 + 38*x^6 - 34*x^5 - 87*x^4 + 94*x^3 - 30*x^2 + x + 1)). - _Sean A. Irvine_, Sep 18 2018
%t CoefficientList[Series[(49 x^16 + 49 x^15 - 745 x^14 - 990 x^13 + 4108 x^12 + 10320 x^11 - 994 x^10 - 12122 x^9 + 2071 x^8 + 433 x^7 + 6952 x^6 - 7424 x^5 + 3184 x^4 - 583 x^3 - 5 x^2 + 15 x-1) / ((7 x^8 - 19 x^7 - 22 x^6 + 98 x^5 + 39 x^4 + 38 x^3 - 60 x^2 + 17 x - 1) (7 x^8 + 33 x^7 + 38 x^6 - 34 x^5 - 87 x^4 + 94 x^3 - 30 x^2 + x + 1)), {x, 0, 33}], x] (* _Vincenzo Librandi_, Sep 18 2018 *)
%Y Cf. A013990, A013991, A013993, A013994, A013995, A013996, A013997.
%K nonn
%O 0,3
%A _Dan Hoey_
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