OFFSET
1,2
PROG
(PARI) v=[1]; n=1; while(n<10^6, s=-1+n*prod(i=1, #v, v[i]); if(issquare(s)&&! vecsearch(vecsort(v), n), v=concat(v, n); n=0); n++); v
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Derek Orr, Jun 22 2015
EXTENSIONS
a(9)-a(11) from Giovanni Resta, Jun 22 2015
STATUS
approved