A378934 Number of minimal edge cuts in the 4 X n grid graph.
3, 28, 146, 627, 2471, 9292, 33878, 120771, 423251, 1463908, 5011690, 17021179, 57450167, 192966908, 645696454, 2154226075, 7170606795, 23825657596, 79055534746, 262031761435, 867792229799, 2872103661988, 9501035284286, 31417942222787, 103862506390523, 343276150243020
Offset: 1
Keywords
Links
- Andrew Howroyd, Table of n, a(n) for n = 1..200
- Index entries for linear recurrences with constant coefficients, signature (10,-37,59,-27,-25,21,5,-4,-1).
Formula
G.f.: x*(3 - 2*x - 23*x^2 + 26*x^3 + 32*x^4 - 2*x^5 - 29*x^6 - 18*x^7 - 3*x^8)/((1 - x)^3*(1 - 2*x - x^2)^2*(1 - 3*x - x^2)).
a(n) = 10*a(n-1) - 37*a(n-2) + 59*a(n-3) - 27*a(n-4) - 25*a(n-5) + 21*a(n-6) + 5*a(n-7) - 4*a(n-8) - a(n-9) for n >= 10.
a(n) = A166766(n)/2.