|
Search: id:A097073
|
|
|
| A097073 |
|
Expansion of (1-x+2x^2)/((1+x)(1-2x)). |
|
+0
4
|
|
| 1, 0, 4, 4, 12, 20, 44, 84, 172, 340, 684, 1364, 2732, 5460, 10924, 21844, 43692, 87380, 174764, 349524, 699052, 1398100, 2796204, 5592404, 11184812, 22369620, 44739244, 89478484, 178956972, 357913940, 715827884, 1431655764, 2863311532
(list; graph; listen)
|
|
|
OFFSET
|
0,3
|
|
|
COMMENT
|
Partial sums are A097074. Pairwise sums are {1,1,4,16,32,...} or 2^n-sum{k=0..n, binomial(n,k)(-1)^(n+k)k}.
|
|
FORMULA
|
a(n)=A001045(n+1)+(-1)^n-0^n; a(n)=2*A078008(n)-0^n; a(n)=2*2^n/3+4(-1)^n/3-0^n.
a(2n+1)+a(2n+2) = A000302(n+1). - Paul Curtz (bpcrtz(AT)free.fr), Jun 30 2008
|
|
CROSSREFS
|
Cf. A046055.
Sequence in context: A053415 A079902 A120033 this_sequence A019085 A106232 A038804
Adjacent sequences: A097070 A097071 A097072 this_sequence A097074 A097075 A097076
|
|
KEYWORD
|
easy,nonn,new
|
|
AUTHOR
|
Paul Barry (pbarry(AT)wit.ie), Jul 22 2004
|
|
|
Search completed in 0.002 seconds
|
