OFFSET
1,1
COMMENTS
Please, refer to the general explanation in A212697.
This sequence is for base b=7 (see formula), corresponding to spin S=(b-1)/2=3.
LINKS
Stanislav Sykora, Table of n, a(n) for n = 1..100
Stanislav Sýkora, Magnetic Resonance on OEIS, Stan's NMR Blog (Dec 31, 2014), Retrieved Nov 12, 2019.
Index entries for linear recurrences with constant coefficients, signature (14,-49).
FORMULA
a(n) = n*(b-1)*b^(n-1). For this sequence, set b=7.
From Colin Barker, Jun 16 2015: (Start)
a(n) = 14*a(n-1) - 49*a(n-2) for n > 2.
G.f.: 6*x/(7*x-1)^2. (End)
From Elmo R. Oliveira, May 14 2025: (Start)
E.g.f.: 6*x*exp(7*x).
From Amiram Eldar, Oct 27 2025: (Start)
Sum_{n>=1} 1/a(n) = (7/6)*log(7/6).
Sum_{n>=1} (-1)^(n+1)/a(n) = (7/6)*log(8/7). (End)
MATHEMATICA
LinearRecurrence[{14, -49}, {6, 84}, 20] (* Harvey P. Dale, Aug 02 2016 *)
PROG
(PARI) mtrans(n, b) = n*(b-1)*b^(n-1);
for (n=1, 100, write("b212701.txt", n, " ", mtrans(n, 7)))
(PARI) Vec(6*x/(7*x-1)^2 + O(x^100)) \\ Colin Barker, Jun 16 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Stanislav Sykora, May 25 2012
STATUS
approved
