OFFSET
3,1
COMMENTS
The second term is the number of nets in a general regular right 4-prism, not in a cube.
LINKS
Takashi Horiyama and Wataru Shoji, The Number of Different Unfoldings of Polyhedra. In: L. Cai, S.-W. Cheng, and T.-W. Lam (Eds.): ISAAC2013, LNCS 8283, pp. 623-633, Springer-Verlag, 2013.
FORMULA
a(n) = 1/(8*sqrt(3))*( 2*sqrt(3)*n + sqrt(3)*(2 + sqrt(3))^n + (2 + sqrt(3))^floor(n/2)*(4+2*sqrt(3)) + (2 - sqrt(3))^floor(n/2)*(2*sqrt(3) - 4) + sqrt(3)*((2 - sqrt(3))^n - 2)) for n >= 3 odd; a(n) = 1/24*(6*n + 3*(2 + sqrt(3))^n + 4*sqrt(3)*(2 + sqrt(3))^(n/2) - 4*sqrt(3)*(2 - sqrt(3))^(n/2) + 3*(2 - sqrt(3))^n - 6) for n >= 4 even. - Humberto Bortolossi, Mar 31 2017
Empirical g.f.: x^3*(9 - 25*x - 21*x^2 + 96*x^3 - 60*x^4 - 12*x^5 + 17*x^6 - 3*x^7) / ((1 - x)^2*(1 - 4*x + x^2)*(1 - 4*x^2 + x^4)). - Colin Barker, Mar 31 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Toshitaka Suzuki, Mar 22 2005
EXTENSIONS
More terms from Alois P. Heinz, Mar 31 2017
STATUS
approved