OFFSET
1,2
FORMULA
MATHEMATICA
2 Prepend[Select[Range@ 82, ! PrimeQ@ # &], 0] (* Michael De Vlieger, Feb 20 2017 *)
PROG
(PARI) isok(n) = !(n%2) && !isprime(n/2); \\ Michel Marcus, Feb 20 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Juri-Stepan Gerasimov, Apr 08 2010, Apr 11 2010
EXTENSIONS
Entries checked by R. J. Mathar, Apr 16 2010
STATUS
approved