OFFSET
1,2
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
For n=6, a(6) = 8; binary expansion of 8 = 1000 (nonprime).
MAPLE
remove(t -> isprime(convert(t, binary)), [$1..100]); # Robert Israel, Jun 13 2017
MATHEMATICA
Select[Range[80], !PrimeQ[FromDigits[IntegerDigits[#, 2]]]&] (* Harvey P. Dale, May 10 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Mar 19 2010
EXTENSIONS
Corrected and extended by Harvey P. Dale, May 10 2012
STATUS
approved