OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..1000
FORMULA
Sum_{n>=1} 1/a(n) = 5/12. - Amiram Eldar, Jul 27 2023
MATHEMATICA
seq[max_] := Union[Join[7^Range[Floor[Log[7, max]]], Flatten@ Table[2^i*5^j, {i, 1, Log2[max]}, {j, 1, Log[5, max/2^i]}]]]; seq[40000] (* Amiram Eldar, Jul 27 2023 *)
PROG
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
M. F. Hasler, Jul 20 2023
STATUS
approved