A175541 A007505 in binary.

10, 101, 1011, 10111, 101111, 10111111, 101111111, 1011111111111, 10111111111111111111, 101111111111111111111111111111111111, 1011111111111111111111111111111111111111

Offset

1,1

Comments

Primes of the form 10, 101, 1011, 10111,..

Links

Table of n, a(n) for n=1..11.

Formula

A002235(n)=A091997(n)-A000012(n)=A000120(A007505(n))-A023416(A007505(n)).

Example

a(12)=101111111111111111111111111111111111111111111.

Mathematica

FromDigits/@Select[Table[PadRight[{1, 0}, n, 1], {n, 0, 50}], PrimeQ[ FromDigits[ #, 2]]&] (* Harvey P. Dale, Nov 12 2011 *)

Crossrefs

Sequence in context: A267623 A283508 A261200 * A180175 A267526 A261199

Adjacent sequences: A175538 A175539 A175540 * A175542 A175543 A175544

Keyword

nonn,base

Author

Juri-Stepan Gerasimov, Jun 24 2010

Status

approved