OFFSET
1,2
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
FORMULA
Sum_{n>=1} 1/a(n) = (4*6)/((4-1)*(6-1)) = 8/5. - Amiram Eldar, Sep 24 2020
a(n) ~ exp(sqrt(2*log(4)*log(6)*n)) / sqrt(24). - Vaclav Kotesovec, Sep 24 2020
MATHEMATICA
f[upto_]:=Module[{max4=Floor[Log[upto]/Log[4]], max6 = Floor[ Log[ upto]/ Log[6]], seq}, seq=Union[4^First[#] 6^Last[#]&/@Tuples[ {Range[ 0, max4], Range[ 0, max6]}]]; Select[seq, #<=upto&]]; f[300000] (* Harvey P. Dale, Mar 05 2011 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
STATUS
approved