|
| |
|
|
A107684
|
|
Union of sequences 2^k-1, 2^k and 2^k+1.
|
|
2
| |
|
|
0, 1, 2, 3, 4, 5, 7, 8, 9, 15, 16, 17, 31, 32, 33, 63, 64, 65, 127, 128, 129, 255, 256, 257, 511, 512, 513, 1023, 1024, 1025, 2047, 2048, 2049, 4095, 4096, 4097, 8191, 8192, 8193, 16383, 16384, 16385, 32767, 32768, 32769, 65535, 65536, 65537, 131071
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,3
|
|
|
COMMENTS
| Subsequence of A107686.
|
|
|
FORMULA
| a(n) = if n<=2 then n else 2^(floor(n/3)+1) + n mod 3 - 1. - Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jun 05 2005
G.f.:-x*(1+3*x+6*x^2+7*x^3+6*x^4+4*x^5+2*x^6)/((2*x^3-1)*(x^2+x+1)) [From Maksym Voznyy (voznyy(AT)mail.ru), Aug 12 2009]
|
|
|
CROSSREFS
| Cf. A000225, A000079, A000051.
Sequence in context: A102363 A201816 A155900 * A111796 A039124 A056759
Adjacent sequences: A107681 A107682 A107683 * A107685 A107686 A107687
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), May 20 2005
|
|
|
EXTENSIONS
| Description corrected by Henrik Lundquist, Jun 06 2005
|
| |
|
|
