login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A103127 Numbers congruent to {-1, 1, 3, 5} mod 16. 4
1, 3, 5, 15, 17, 19, 21, 31, 33, 35, 37, 47, 49, 51, 53, 63, 65, 67, 69, 79, 81, 83, 85, 95, 97, 99, 101, 111, 113, 115, 117, 127, 129, 131, 133, 143, 145, 147, 149, 159, 161, 163, 165, 175, 177, 179, 181, 191, 193, 195, 197, 207, 209, 211, 213, 223, 225, 227, 229, 239, 241 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Agrees with A103192 for the first 511 terms, but then diverges (see comment in A103192). - Bruno Berselli, Dec 01 2016

LINKS

Table of n, a(n) for n=1..61.

David Applegate, Benoit Cloitre, Philippe Deléham and N. J. A. Sloane, Sloping binary numbers: a new sequence related to the binary numbers, J. Integer Seq. 8 (2005), no. 3, Article 05.3.6, 15 pp [pdf, ps].

FORMULA

a(n) = 2*A047527(n) + 1.

From R. J. Mathar, Aug 30 2008: (Start)

O.g.f.: x*(1 + 2*x + 2*x^2 + 10*x^3 + x^4)/((1 - x)^2*(1 + x)*(1 + x^2)).

a(n) = a(n-4) + 16. (End)

a(n) = (1+i)*i^n - (-1)^n + 4*n + (1-i)*(-i)^n, with n>=0 and i=sqrt(-1). - Paolo P. Lava, Nov 19 2008

a(n) = 2*A047476(n+1) - 1. - Philippe Deléham, Dec 01 2016

PROG

(Haskell)

a103127 n = a103127_list !! (n-1)

a103127_list = [x | x <- [1..], x `mod` 16 `elem` [1, 3, 5, 15]]

-- Reinhard Zumkeller, Jul 21 2012

CROSSREFS

Cf. A047527, A103192.

Sequence in context: A102582 A089168 * A103192 A097856 A071593 A192794

Adjacent sequences:  A103124 A103125 A103126 * A103128 A103129 A103130

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Mar 25 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 | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 17 19:36 EDT 2018. Contains 316293 sequences. (Running on oeis4.)