OFFSET
0,2
EXAMPLE
a(2) = 2^2 * 3 * 11 = 132 containing 2 and 3;
a(3) = 3 * 5 * 7^2 = 735 containing 3, 5 and 7;
a(4) = 2^2 * 3 * 13 * 137 = 21372 containing 2, 3, 13 and 137;
a(5) = 2 * 3 * 7^2 * 13 * 71 = 271362 containing 2, 3, 7, 13 and 71.
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
Reinhard Zumkeller, Jul 30 2007
EXTENSIONS
Offset changed by and a(6)-a(8) from Giovanni Resta, Sep 06 2018
STATUS
approved