1,5,18,66,280,1420

• 8544
  sequence r like---> a(n)= n*(a(n-1)+4) & a(0)=1
  a(1)= 1*(a(1-1)+4)=5
  a(2)= 2*(a(2-1)+4)=2*(5+4)=18
  a(3)= 3*(a(3-1)+4)=3*(18+4)=66
  similarly
  a(4)=4*(a(3)+4)=4*(66+4)=280
  a(5)=5*(280+4)=1420
  a(6)=6*(1420+4)=6*1424= 8544 (ans)
• 8 years agoHelpfull: Yes(1) No(0)