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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A163293 a(n) = n-th prime minus (number of bits in binary expansion of n-th prime). 2
0, 1, 2, 4, 7, 9, 12, 14, 18, 24, 26, 31, 35, 37, 41, 47, 53, 55, 60, 64, 66, 72, 76, 82, 90, 94, 96, 100, 102, 106, 120, 123, 129, 131, 141, 143, 149, 155, 159, 165, 171, 173, 183, 185, 189, 191, 203, 215, 219, 221, 225, 231, 233, 243, 248, 254, 260, 262, 268, 272 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Number of bits in binary expansion of n-th prime = A035100.

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A000040(n) - A035100(n).

EXAMPLE

a(6) = 13 - 4 = 9;

a(7) = 17 - 5 = 12.

MAPLE

A000040 := proc(n) ithprime(n) ; end: A035100 := proc(n) max(1, ilog2(A000040(n))+1) ; end: A163293 := proc(n) A000040(n)-A035100(n) ; end: seq(A163293(n), n=1..100) ; # R. J. Mathar, Jul 26 2009

MATHEMATICA

Table[Prime[n] - Length[IntegerDigits[Prime[n], 2]], {n, 100}] (* G. C. Greubel, Dec 17 2016 *)

PROG

(PARI) for(n=1, 60, p=prime(n); print1(p-#binary(p), ", ")) \\ Washington Bomfim Jan 18 2011

CROSSREFS

Cf. A000040, A035100.

Sequence in context: A087733 A065027 A165994 * A188045 A247912 A186321

Adjacent sequences:  A163290 A163291 A163292 * A163294 A163295 A163296

KEYWORD

nonn,base,easy

AUTHOR

Juri-Stepan Gerasimov, Jul 24 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 December 7 09:33 EST 2019. Contains 329843 sequences. (Running on oeis4.)