This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A280154 a(n) = 5*Lucas(n). 6

%I

%S 10,5,15,20,35,55,90,145,235,380,615,995,1610,2605,4215,6820,11035,

%T 17855,28890,46745,75635,122380,198015,320395,518410,838805,1357215,

%U 2196020,3553235,5749255,9302490,15051745,24354235,39405980,63760215,103166195,166926410,270092605,437019015

%N a(n) = 5*Lucas(n).

%C Fibonacci sequence beginning 10, 5.

%C After 5, the sequence provides the 3rd column of the rectangular array in A213590.

%C After 5, all terms belong to A191921 because a(n) = Lucas(n+4) - 3*Lucas(n-1).

%C From _G. C. Greubel_, Dec 27 2016: (Start)

%C a(n) mod 3 yields (1,2,0,2,2,1,0,1), repeated, and is given as A082115.

%C a(n) mod 6 yields (4,5,3,2,5,1,0,1,1,2,3,5,2,1,3,4,1,5,0,5,5,4,3,1) and is given as A082117. (End)

%H Bruno Berselli, <a href="/A280154/b280154.txt">Table of n, a(n) for n = 0..1000</a>

%H Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a>

%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (1,1).

%F G.f.: 5*(2 - x)/(1 - x - x^2).

%F a(n) = a(n-1) + a(n-2) for n>1.

%F a(n) = Fibonacci(n+5) + Fibonacci(n-5), with Fibonacci(-i) = -(-1)^i*Fibonacci(i) for the negative indices.

%p F := n -> combinat:-fibonacci(n):

%p seq(F(n+5) + F(n-5), n=0..38); # _Peter Luschny_, Dec 29 2016

%t Table[5 LucasL[n], {n, 0, 40}]

%o (PARI) vector(40, n, n--; fibonacci(n+5)+fibonacci(n-5))

%o (MAGMA) [5*Lucas(n): n in [0..40]];

%o (Sage)

%o def A280154():

%o x, y = 10, 5

%o while true:

%o yield x

%o x, y = y, x + y

%o a = A280154(); print [a.next() for _ in range(39)] # _Peter Luschny_, Dec 29 2016

%Y Subsequence of A084176.

%Y Cf. A022088: 5*Fibonacci(n).

%Y Cf. A022359: Lucas(n+5) + Lucas(n-5).

%Y Cf. A000032, A000045, A191921, A213590.

%Y Cf. sequences with formula Fibonacci(n+k) + Fibonacci(n-k): A006355 (k=0, without the initial 1), A000032 (k=1), A022086 (k=2), A022112 (k=3, with an initial 4), A022090 (k=4), this sequence (k=5), A022352 (k=6).

%K nonn,easy

%O 0,1

%A _Bruno Berselli_, Dec 27 2016

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified October 22 21:09 EDT 2018. Contains 316505 sequences. (Running on oeis4.)