The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A180664 Golden Triangle sums: a(n)=a(n-1)+A001654(n+1) with a(0)=0. 8
 0, 2, 8, 23, 63, 167, 440, 1154, 3024, 7919, 20735, 54287, 142128, 372098, 974168, 2550407, 6677055, 17480759, 45765224, 119814914, 313679520, 821223647, 2149991423, 5628750623, 14736260448, 38580030722, 101003831720 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS The a(n+1) (terms doubled) are the Kn13 sums of the Golden Triangle A180662. See A180662 for information about these knight and other chess sums. LINKS Index entries for linear recurrences with constant coefficients, signature (3, 0, -3, 1). FORMULA a(n) = a(n-1)+A001654(n+1) with a(0)=0. a(n+1) = add(A180662(2*n-k+2,k+2),k=0..floor(n)). a(n) = (-15+(-1)^(-n)+(6-2*A)*A^(-n-1)+(6-2*B)*B^(-n-1))/10 with A=(3+sqrt(9-4))/2 and B=(3-sqrt(9-4))/2. GF(x) = (2*x+2*x^2-x^3)/(1-3*x-x^4+3*x^3). MAPLE nmax:=26: with(combinat): for n from 0 to nmax+1 do A001654(n):=fibonacci(n) * fibonacci(n+1) od: a(0):=0: for n from 1 to nmax do a(n) := a(n-1)+A001654(n+1) od: seq(a(n), n=0..nmax); CROSSREFS Cf. A064831, A180664, A180665, A115730, A180666. Sequence in context: A079460 A154144 A255942 * A294959 A290926 A018042 Adjacent sequences:  A180661 A180662 A180663 * A180665 A180666 A180667 KEYWORD easy,nonn AUTHOR Johannes W. Meijer, Sep 21 2010 STATUS approved

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

Last modified April 3 04:21 EDT 2020. Contains 333195 sequences. (Running on oeis4.)