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%I #37 Aug 25 2022 05:20:04
%S 34,241,1582,10204,65197,415076,2638366,16759249,106427154,675771276,
%T 4290678337,27242281044,172964658642,1098170541121,6972388689086,
%U 44268329738124,281063582763949,1784497634505876,11329933410988622,71934748718289089,456720074988060962
%N Number of restricted forests in Moebius ladder M_n.
%H Peter J. Taylor, <a href="/A020872/b020872.txt">Table of n, a(n) for n = 2..500</a>
%H Code Golf Stack Exchange, <a href="https://codegolf.stackexchange.com/q/182201/53884">Counting the number of restricted forests on the Möbius ladder of length n</a>
%H Peter Kagey, <a href="/A020872/a020872.png">Example the a(2) = 34 restricted forests on M_2</a>
%H J. P. McSorley, <a href="http://dx.doi.org/10.1016/S0012-365X(97)00086-1">Counting structures in the Moebius ladder</a>, Discrete Math., 184 (1998), 137-164.
%F For large n, (4.8820)^n < a(n) < (6.4188)^n (Th. 10.1.). - C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 17 2005
%F a(n) is asymptotic to c^n where c = 6.349088... is the inverse of the root of x^4 - x^3 - 4 x^2 + 7 x - 1 of smallest modulus. - _Peter Kagey_, May 10 2019
%F a(n) = 11*a(n-1) - 34*a(n-2) + 23*a(n-3) + 43*a(n-4) - 56*a(n-5) - 3*a(n-6) + 25*a(n-7) - 6*a(n-8) - 3*a(n-9) + a(n-10). - _Peter J. Taylor_, Mar 30 2019
%F G.f.: (4x^9 - 11x^8 - 31x^7 + 108x^6 - 264x^4 + 214x^3 + 87x^2 - 133x + 34)/(-x^10 + 3x^9 + 6x^8 - 25x^7 + 3x^6 + 56x^5 - 43x^4 - 23x^3 + 34x^2 - 11x + 1). - _Peter Kagey_, May 10 2019
%K nonn
%O 2,1
%A _N. J. A. Sloane_
%E a(5)-a(12) from _Peter J. Taylor_, Mar 26 2019
%E a(13)-a(22) from _Peter J. Taylor_, Mar 30 2019
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