login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A140891 Binary encoding of the prime-ness of the 6 integers r+14*n with remainder r=1, 3, 5, 9, 11 or 13. 0
9, 49, 20, 42, 41, 20, 27, 33, 62, 10, 39, 21, 11, 39, 60, 30, 49, 28, 43, 41, 28, 31, 49, 55, 14, 53, 53, 42, 51, 29, 14, 51, 22, 58, 45, 22, 59, 57, 55, 46, 37, 29, 11, 43, 60, 14, 53, 60, 42, 59, 54, 27, 43, 54, 26, 61, 29, 15, 39, 28, 31, 49, 23, 58, 47, 54, 27, 53, 62, 42 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Classify all integers 14n+r with r= 1, 3, 5, 9, 11 or 13 as nonprime or prime and assign hit positions 0=LSB, 1, 2, 3, 4, 5=MSB to the 6 remainders in the same order. Raise the bit if 14n+r is nonprime, erase it if 14n+r is prime.

The sequence interprets this as a number in base 2 and shows the decimal representation.

LINKS

Table of n, a(n) for n=0..69.

EXAMPLE

For n=2, the 6 numbers 29 (r=1), 31 (r=3), 33 (r=5), 37 (r=9), 39 (r=11) and 41 (r=13) are prime, prime, nonprime, prime, nonprime, prime, which is rendered into the binary 001010 = 2^2+2^4=4+16=20=a(2).

MATHEMATICA

f[n_]:=FromDigits[1-Boole[PrimeQ[({13, 11, 9, 5, 3, 1}+14n)]], 2]; Table[f[n], {n, 0, 100}] (* Ray Chandler, Feb 20 2009 *)

CROSSREFS

Cf. A105052, A140387.

Sequence in context: A293095 A283092 A249780 * A072461 A181607 A012260

Adjacent sequences:  A140888 A140889 A140890 * A140892 A140893 A140894

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jul 07 2008

EXTENSIONS

Corrected and extended by Ray Chandler, Feb 20 2009

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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 15 17:45 EDT 2021. Contains 348033 sequences. (Running on oeis4.)