OFFSET
1,5
FORMULA
a(n)=(a(n-2)+a(n-3))*a(n-1)/a(n-4), n>4. a(1)=a(2)=a(3)=a(4)=1.
MATHEMATICA
RecurrenceTable[{a[1]==a[2]==a[3]==a[4]==1, a[n]==(a[n-2]+a[n-3]) a[n-1]/a[n-4]}, a, {n, 20}] (* Harvey P. Dale, Mar 12 2015 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Dec 13 2002
EXTENSIONS
One more term (a(18)) from Harvey P. Dale, Mar 12 2015
STATUS
approved