OFFSET
1,2
COMMENTS
The number after 1 has to be 4, because the product 1*4 must be composite.
Then 2 is OK, because 4*2 = 8 is composite.
Then 3, because 2*3 = 6 is composite, and so on.
Note that 14 is the term after 9 because 10 is now the smallest candidate, but 10 has a 0 digit, 11 consists of two unit digits, and 12 and 13 have digit products 2 and 3, which are prime. - _T. D. Noe_, Apr 25 2012
CROSSREFS
KEYWORD
nonn,base,easy,nice
AUTHOR
_Jim Nastos_ and _Eric Angelini_, Apr 22 2012
STATUS
approved