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A332750
The number of flips to go from Hamiltonian cycle alpha_n to beta_n in the Cameron graph of size n using Thomason's algorithm.
2
11, 65, 265, 1005, 3749, 13927, 51683, 191735, 711243, 2638305, 9786545, 36302213, 134659381, 499505271, 1852863915, 6873009871, 25494729643, 94570101217, 350798151929, 1301249991357, 4826854219941, 17904723777319, 66415748007763, 246362448161159, 913856392265003
OFFSET
1,1
FORMULA
G.f.: z(1+z)(11+10z+6z^2+4z^3+z^4)/((1-z)(1-3z-2z^2-2z^3-z^4-z^5)).
a(n) = 4*a(n-1) - a(n-2) - a(n-4) - a(n-6) for n>6. - Colin Barker, Feb 22 2020
MATHEMATICA
LinearRecurrence[{4, -1, 0, -1, 0, -1}, {11, 65, 265, 1005, 3749, 13927}, 20] (* Jinyuan Wang, Feb 22 2020 *)
PROG
(PARI) Vec(z*(1+z)*(11+10*z+6*z^2+4*z^3+z^4)/((1-z)*(1-3*z-2*z^2-2*z^3-z^4-z^5)) + O(z^30)) \\ Jinyuan Wang, Feb 22 2020
CROSSREFS
Cf. A332751 (number of flips from beta_n to gamma_n, same growth rate).
Sequence in context: A233164 A215445 A184055 * A161459 A162288 A161776
KEYWORD
nonn,easy
AUTHOR
Filip Stappers, Feb 22 2020
EXTENSIONS
More terms from Jinyuan Wang, Feb 22 2020
STATUS
approved