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A212702
Main transitions in systems of n particles with spin 7/2.
8
7, 112, 1344, 14336, 143360, 1376256, 12845056, 117440512, 1056964608, 9395240960, 82678120448, 721554505728, 6253472382976, 53876069761024, 461794883665920, 3940649673949184, 33495522228568064, 283726776524341248, 2395915001761103872, 20176126330619822080
OFFSET
1,1
COMMENTS
Please, refer to the general explanation in A212697.
This sequence is for base b=8 (see formula), corresponding to spin S=(b-1)/2=7/2.
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=8.
From Colin Barker, Jun 16 2015: (Start)
a(n) = 16*a(n-1) - 64*a(n-2) for n > 2.
G.f.: 7*x/(8*x-1)^2. (End)
From Elmo R. Oliveira, May 14 2025: (Start)
E.g.f.: 7*x*exp(8*x).
a(n) = 7*A053539(n) = A008589(n)*A001018(n-1). (End)
From Amiram Eldar, Oct 27 2025: (Start)
Sum_{n>=1} 1/a(n) = (8/7)*log(8/7).
Sum_{n>=1} (-1)^(n+1)/a(n) = (8/7)*log(9/8). (End)
MATHEMATICA
LinearRecurrence[{16, -64}, {7, 112}, 30] (* Harvey P. Dale, Feb 11 2016 *)
PROG
(PARI) mtrans(n, b) = n*(b-1)*b^(n-1);
for (n=1, 100, write("b212702.txt", n, " ", mtrans(n, 8)))
(PARI) Vec(7*x/(8*x-1)^2 + O(x^100)) \\ Colin Barker, Jun 16 2015
CROSSREFS
Cf. A001787, A212697, A212698, A212699, A212700, A212701, A212703, A212704 (b = 2, 3, 4, 5, 6, 7, 9, 10).
Sequence in context: A117795 A163700 A094219 * A217223 A067404 A129030
KEYWORD
nonn,easy
AUTHOR
Stanislav Sykora, May 25 2012
STATUS
approved