OFFSET
0,3
COMMENTS
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..950
Index entries for linear recurrences with constant coefficients, signature (7,42).
FORMULA
a(n+1) = Sum_{k=0..n} A154929(n,k)*6^(n-k).
G.f.: (1 - 6*x - 36*x^2)/(1 - 7*x - 42*x^2). - G. C. Greubel, Apr 20 2021
MATHEMATICA
LinearRecurrence[{7, 42}, {1, 1, 13}, 31] (* G. C. Greubel, Apr 20 2021 *)
CoefficientList[Series[(1-6x-36x^2)/(1-7x-42x^2), {x, 0, 20}], x] (* Harvey P. Dale, Jan 14 2022 *)
PROG
(Magma) I:=[1, 13]; [1] cat [n le 2 select I[n] else 7*(Self(n-1) +6*Self(n-2)): n in [1..30]]; // G. C. Greubel, Apr 20 2021
(Sage)
def A154999_list(prec):
P.<x> = PowerSeriesRing(ZZ, prec)
return P( (1-6*x-36*x^2)/(1-7*x-42*x^2) ).list()
A154999_list(30) # G. C. Greubel, Apr 20 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
Philippe Deléham, Jan 18 2009
EXTENSIONS
More terms from Philippe Deléham, Jan 27 2009
Corrected by D. S. McNeil, Aug 20 2010
STATUS
approved