OFFSET
1,1
COMMENTS
These are the exponents on 3 in numbers of the form (3^r)*(7^s) of the main sequence.
EXAMPLE
A217410(1)=(3^37)*(7^10), so this sequence's first term is 37.
CROSSREFS
KEYWORD
nonn,base,less
AUTHOR
James G. Merickel, Oct 02 2012
STATUS
approved