[go: up one dir, main page]

login
A084330
a(0)=0, a(1)=1, a(n) = 31*a(n-1) - 29*a(n-2).
2
0, 1, 31, 932, 27993, 840755, 25251608, 758417953, 22778659911, 684144336604, 20547893297305, 617144506454939, 18535590794481264, 556706123941725953, 16720357709153547887, 502186611389449931860, 15082894579507494998937, 453006320234438296943107
OFFSET
0,3
FORMULA
a(n) = (1/13)*sum(k=0, n, binomial(n, k)*F(7*k)) where F(k) denotes the k-th Fibonacci number.
G.f.: x / (29*x^2-31*x+1). - Colin Barker, Jun 26 2013
MAPLE
f:=proc(n) option remember; if n <=1 then n else 31*f(n-1)-29*f(n-2); fi; end;
MATHEMATICA
LinearRecurrence[{31, -29}, {0, 1}, 30] (* Harvey P. Dale, Jul 11 2014 *)
PROG
(PARI) a(n)=(1/13)*sum(k=0, n, binomial(n, k)*fibonacci(7*k))
(Magma) I:=[0, 1]; [n le 2 select I[n] else 31*Self(n-1)-29*Self(n-2): n in [1..20]]; // Vincenzo Librandi, Jun 02 2015
CROSSREFS
Cf. A030191.
Sequence in context: A170712 A170750 A218733 * A238993 A171336 A200442
KEYWORD
nonn,easy
AUTHOR
Benoit Cloitre, Jun 21 2003
EXTENSIONS
Corrected by N. J. A. Sloane, Sep 16 2005
STATUS
approved