What is the next number of the following sequence
21,77,165,285,......

• 77-21=56
  165-77=88
  285-165=120
  56+32=88
  88+32=120
  120+32=152
  so ans is 285+152=437
  
  
• 10 years agoHelpfull: Yes(6) No(0)
• 21=3*7.....7+4=11
  77=7*11.....11+4=15
  165=11*15....15+4=19
  285=15*19....19+4=23
  next term= 19*23=437
• 10 years agoHelpfull: Yes(2) No(0)
• 21=(5*5)-4
  77=(9*9)-4
  165=(13*13)-4
  285=(17*17)-4
  as process is done with the numbers 5,9,13,17..with difference "4" next num is 17+4=21
  437=(21*21)-4
  hence next num in the given series is "437"..
• 10 years agoHelpfull: Yes(2) No(0)
• 77-21=56
  165-77=88
  285-165=120
  now,55-86=32
  120-88=32
  so,120+32=152 and last number is 152+285=437
• 10 years agoHelpfull: Yes(1) No(0)
• 437
  285+152=437
• 10 years agoHelpfull: Yes(0) No(1)
• 
  series= 21,77,165,285,....
  77-21 = 56
  165-77 = 88
  285-165 = 120
  285+(120+32) = 437
• 10 years agoHelpfull: Yes(0) No(0)
• 21,77,165,285,437
• 4 years agoHelpfull: Yes(0) No(0)