|
Search: id:A122756
|
|
|
| A122756 |
|
Odd indexed terms, a(n) = 2^n. Even indexed terms, a(n) = 2^n + 2^(n-1). |
|
+0
3
|
|
| 1, 2, 6, 8, 24, 32, 96, 128, 384, 512, 1536, 2048, 6144, 8192, 24576, 32768, 98304, 131072, 393216, 524288, 1572864, 2097152, 6291456, 8388608, 25165824, 33554432, 100663296, 134217728, 402653184, 536870912, 1610612736, 2147483648
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
Row sums of triangle A133569. - Gary W. Adamson (qntmpkt(AT)yahoo.com), Sep 16 2007
|
|
FORMULA
|
a(n) =If[Mod[n, 2] == 0, 2^(n + 1), 2^n + 2^(n + 1)]=2*A084221[n]
a(0)=1, a(1)=2, a(2)=6, a(n)=4*a(n-2) for n>=3 . G.f.: (1+2*x+2*x^2)/(1-4*x^2) - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Dec 14 2007
|
|
MATHEMATICA
|
f[n_] := If[Mod[n, 2] == 0, 2^(n + 1), 2^n + 2^(n + 1)] Table[f[n], {n, 0, 30}]
|
|
CROSSREFS
|
Cf. A000079, A084221, A133569.
Sequence in context: A068496 A081957 A122758 this_sequence A116083 A115506 A057852
Adjacent sequences: A122753 A122754 A122755 this_sequence A122757 A122758 A122759
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Roger Bagula (rlbagulatftn(AT)yahoo.com), Sep 21 2006
|
|
EXTENSIONS
|
Edited by njas, Dec 14 2007
|
|
|
Search completed in 0.002 seconds
|
