OFFSET
1,3
COMMENTS
These are the numbers that appear at least once in A007425 (the number of ordered factorizations of n as n = r*s*t). - Matthew Vandermast, Jul 26 2003
Contains A085780 as a subsequence (exactly 2 factors); 27,54,81,... are the first elements in the complement. - M. F. Hasler, Apr 03 2008
The number of r-orthotopes of any size contained in a n1*n2*...*nr r-orthotope, where a(n)=t(n1)*t(n2)*...*t(nr) and t(k)=A000217(k). - Dimitri Boscainos, Aug 27 2015
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000
EXAMPLE
54 = 6*3*3 = t(3)*t(2)*t(2).
CROSSREFS
KEYWORD
nonn
AUTHOR
Jon Perry, Jul 23 2003
EXTENSIONS
More terms from Max Alekseyev and Jon E. Schoenfield, Sep 04 2009
STATUS
approved