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A212703
Main transitions in systems of n particles with spin 4.
9
8, 144, 1944, 23328, 262440, 2834352, 29760696, 306110016, 3099363912, 30993639120, 306837027288, 3012581722464, 29372671794024, 284688972772848, 2745215094595320, 26354064908115072, 252010745683850376, 2401514164751985936, 22814384565143866392
OFFSET
1,1
COMMENTS
Please, refer to the general explanation in A212697.
This sequence is for base b=9 (see formula), corresponding to spin S=(b-1)/2=4.
LINKS
Stanislav Sýkora, Magnetic Resonance on OEIS, Stan's NMR Blog (Dec 31, 2014), Retrieved Nov 12, 2019.
FORMULA
a(n) = n*(b-1)*b^(n-1). For this sequence, set b=9.
a(n) = 18*a(n-1)-81*a(n-2). - Colin Barker, Jun 16 2015
G.f.: 8*x / (9*x-1)^2. - Colin Barker, Jun 16 2015
MATHEMATICA
LinearRecurrence[{18, -81}, {8, 144}, 30] (* Harvey P. Dale, Jun 28 2017 *)
PROG
(PARI) mtrans(n, b) = n*(b-1)*b^(n-1);
for (n=1, 100, write("b212703.txt", n, " ", mtrans(n, 9)))
(PARI) Vec(8*x/(9*x-1)^2 + O(x^100)) \\ Colin Barker, Jun 16 2015
(PARI) a(n)=8*n*9^(n-1) \\ Charles R Greathouse IV, Jun 16 2015
CROSSREFS
Cf. A001787, A212697, A212698, A212699, A212700, A212701, A212702, A212704 (b = 2, 3, 4, 5, 6, 7, 8, 10).
Sequence in context: A241229 A274730 A263604 * A065409 A061899 A134492
KEYWORD
nonn,easy
AUTHOR
Stanislav Sykora, May 25 2012
STATUS
approved