The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A108177 Integers of the form 2^(4n-1) or 2^(4n), n>0 and their immediate neighbors, together with -1, 0 and 1. 0
 -1, 0, 1, 7, 8, 9, 15, 16, 17, 127, 128, 129, 255, 256, 257, 2047, 2048, 2049, 4095, 4096, 4097, 32767, 32768, 32769, 65535, 65536, 65537, 524287, 524288, 524289, 1048575, 1048576, 1048577, 8388607, 8388608, 8388609, 16777215, 16777216, 16777217, 134217727, 134217728, 134217729, 268435455 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS These integers are generated as a subset of interesting "areas" in typical microprocessor designs often based on 8, 16, 24, 32, 40, 56, 64 or 80 bits of precision and includes those areas where the sign representation could cause some design error. The numbers -1, 0, 1 represent a special case since they should and will be represented by a higher order number in the limited number space of N bits. LINKS Table of n, a(n) for n=0..42. Index entries for linear recurrences with constant coefficients, signature (-1,-1,0,0,0,16,16,16). FORMULA Union of integers: -1, 0, 1, (2^((4n)-1)) +/- { 0, 1 }, (2^(4n)) +/- { 0, 1 } From Chai Wah Wu, Dec 23 2019: (Start) a(n) = - a(n-1) - a(n-2) + 16*a(n-6) + 16*a(n-7) + 16*a(n-8) for n > 10. G.f.: (-16*x^10 - 32*x^9 - 48*x^8 - 56*x^7 - 48*x^6 - 24*x^5 - 16*x^4 - 8*x^3 + x + 1)/((4*x^3 - 1)*(4*x^3 + 1)*(x^2 + x + 1)). (End) MATHEMATICA Join[{-1, 0, 1}, Sort[ Flatten[ NestList[{# - 1, # + 1} &, Flatten[ Table[{2^(4n - 1), 2^(4n)}, {n, 6}]], 1]]]] (* Robert G. Wilson v, Jun 14 2005 *) CROSSREFS Sequence in context: A076599 A067197 A047523 * A165480 A285468 A060258 Adjacent sequences: A108174 A108175 A108176 * A108178 A108179 A108180 KEYWORD sign,easy AUTHOR Henrik Lundquist (sploinker(AT)sploink.dk), Jun 13 2005 EXTENSIONS Edited by Robert G. Wilson v, Jun 14 2005 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified April 18 02:22 EDT 2024. Contains 371767 sequences. (Running on oeis4.)