|
Search: id:A134927
|
|
|
| A134927 |
|
a(0)=a(1)=1; a(n)=3*(a(n-1)+a(n-2)). |
|
+0
1
|
|
| 1, 1, 6, 21, 81, 306, 1161, 4401, 16686, 63261, 239841, 909306, 3447441, 13070241, 49553046, 187869861, 712268721, 2700415746, 10238053401, 38815407441, 147160382526, 557927369901, 2115263257281, 8019571881546, 30404505416481
(list; graph; listen)
|
|
|
OFFSET
|
0,3
|
|
|
LINKS
|
Joshua Zucker (joshua.zucker(AT)stanfordalumni.org), Feb 23 2008, Table of n, a(n) for n = 0..50
Zerinvary Lajos, Sage Notebooks
|
|
FORMULA
|
O.g.f.: (-1+2*x)/(-1+3*x+3*x^2) . a(n) = A030195(n+1)-2*A030195(n) . - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 31 2008
|
|
PROGRAM
|
sage: from sage.combinat.sloane_functions import recur_gen2 sage: it = recur_gen2(1, 1, 3, 3) sage: [it.next() for i in range(25)] - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Jun 25 2008
|
|
CROSSREFS
|
Cf. A108306.
Sequence in context: A026628 A053768 A108306 this_sequence A088556 A137966 A005498
Adjacent sequences: A134924 A134925 A134926 this_sequence A134928 A134929 A134930
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Rolf Pleisch (r_pleisch(AT)gmx.ch), Jan 29 2008
|
|
EXTENSIONS
|
More terms from Joshua Zucker (joshua.zucker(AT)stanfordalumni.org), Feb 23 2008
|
|
|
Search completed in 0.002 seconds
|
