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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A000038 Twice A000007.
(Formerly M0004)
15
2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Multiplicative with a(p^e) = 0. - Mitch Harris, Jun 09 2005

1 + (-1)^n-th prime. - Juri-Stepan Gerasimov, Oct 29 2009

REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

James Spahlinger, Table of n, a(n) for n = 0..10000

Daniele A. Gewurz and Francesca Merola, Sequences realized as Parker vectors ..., J. Integer Seqs., Vol. 6, 2003.

FORMULA

a(n) = 2*A000007(n) = (-1)^A000040(n) + 1. - Juri-Stepan Gerasimov, Oct 29 2009

PROG

(Haskell)

a000038 n = 2 * a000007 n -- James Spahlinger, Oct 08 2012

(PARI) a(n)=if(n, 0, 2) \\ Charles R Greathouse IV, Oct 09 2012

CROSSREFS

Cf. A007395, A000007.

Sequence in context: A072507 A130779 A130706 * A063667 A228594 A281669

Adjacent sequences:  A000035 A000036 A000037 * A000039 A000040 A000041

KEYWORD

easy,nonn,mult

AUTHOR

N. J. A. Sloane

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 June 26 06:03 EDT 2017. Contains 288754 sequences.