|
Search: id:A163888
|
|
|
| A163888 |
|
a(n) = 2*a(n-2) for n > 2; a(1) = 5, a(2) = 4. |
|
+0
5
|
|
| 5, 4, 10, 8, 20, 16, 40, 32, 80, 64, 160, 128, 320, 256, 640, 512, 1280, 1024, 2560, 2048, 5120, 4096, 10240, 8192, 20480, 16384, 40960, 32768, 81920, 65536, 163840, 131072, 327680, 262144, 655360, 524288, 1310720, 1048576, 2621440, 2097152, 5242880
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
Interleaving of A020714 and A000079 without initial terms 1 and 2.
Binomial transform is A163607, second binomial transform is A163608, third binomial transform is A163609, fourth binomial transform is A163610, fifth binomial transform is A163611.
|
|
FORMULA
|
a(n) = (7-3*(-1)^n)*2^(1/4*(2*n-1+(-1)^n))/2.
G.f.: x*(5+4*x)/(1-2*x^2).
|
|
PROGRAM
|
(MAGMA) [ n le 2 select 6-n else 2*Self(n-2): n in [1..41] ];
|
|
CROSSREFS
|
Cf. A020714 (5*2^n), A000079 (powers of 2), A163607, A163608, A163609, A163610, A163611.
Sequence in context: A086654 A152064 A088482 this_sequence A089520 A163524 A051552
Adjacent sequences: A163885 A163886 A163887 this_sequence A163889 A163890 A163891
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Klaus Brockhaus (klaus-brockhaus(AT)t-online.de), Aug 06 2009
|
|
|
Search completed in 0.002 seconds
|
