OFFSET
1,2
COMMENTS
Sequence consists only of composite numbers.
FORMULA
a(n)=[...[[[[n(1+1/2)](1+1/3)](1+1/5)]...(1+1/p_k)]..., where [x] = floor of x and p_k is the k-th prime; this infinite nested floor product will eventually level-off at a(n). Alternatively, for n>=1, let b(0, n)=n and b(k, n) = floor( b(k-1, n)*(1 + 1/p_k) ), for k=1..m, then a(n)=b(m, n) where m is smallest integer such that p_m > a(n).
EXAMPLE
a(4)=10 since [[[[4(1+1/2)](1+1/3)](1+1/5)](1+1/7)]= [[[6(1+1/3)](1+1/5)](1+1/7)]=[[8(1+1/5)](1+1/7)]=[9(1+1/7)]=10.
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul D. Hanna, Jul 29 2002
STATUS
approved