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!)
A127964 Number of 0's in A127962(n). 3
0, 1, 2, 4, 5, 7, 8, 10, 14, 20, 29, 38, 49, 62, 82, 94, 98, 155, 172, 349, 853, 1307, 1768, 2902, 5249, 5344, 5638, 6194, 7238 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Apparently n such that (2^(2*n+3)+1)/3 is prime. - James R. Buddenhagen, Apr 14 2011

LINKS

Table of n, a(n) for n=1..29.

FORMULA

a(n) = A023416(A000979(n)). - Michel Marcus, Nov 07 2013

MATHEMATICA

b = {}; Do[c = 1 + Sum[2^(2n - 1), {n, 1, x}]; If[PrimeQ[c], AppendTo[b, c]], {x, 0, 1000}]; a = {}; Do[AppendTo[a, FromDigits[IntegerDigits[b[[x]], 2]]], {x, 1, Length[b]}]; d = {}; Do[AppendTo[d, DigitCount[a[[x]], 10, 0]], {x, 1, Length[a]}]; d (*Artur Jasinski*)

CROSSREFS

Cf. A127962, A127961, A000979, A000978, A124400, A126614, A127955, A127956, A127957, A127958, A127936.

Sequence in context: A018519 A050054 A018371 * A269929 A085370 A006693

Adjacent sequences:  A127961 A127962 A127963 * A127965 A127966 A127967

KEYWORD

nonn

AUTHOR

Artur Jasinski, Feb 09 2007

EXTENSIONS

a(22)-a(29) from Vincenzo Librandi, Mar 31 2012

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 11 02:18 EST 2019. Contains 329910 sequences. (Running on oeis4.)