Is this acceptable in recursive formulas?

by Cloudless
Tags: acceptable, formulas, recursive
Cloudless is offline
Jan19-12, 05:09 PM
P: 15
Say for the recursive formula 2, 5, 9, 19 , 37...

Instead of writing it as an = an-1 + * 2 an-2

can you write it as:

an = 2an + (-1)n

Just double checking. I encountered this earlier helping someone and I haven't done recursive formulas in a while..
Phys.Org News Partner Mathematics news on
Researchers help Boston Marathon organizers plan for 2014 race
'Math detective' analyzes odds for suspicious lottery wins
Pseudo-mathematics and financial charlatanism
AlephZero is offline
Jan19-12, 07:53 PM
Sci Advisor
HW Helper
P: 6,344
I think you meant an = 2an-1 + (-1)n

Sure. Your formula is the same as

an = an-1 + (-1)n + an-1
= an-1 + (-1)n + 2an-2 + (-1)n-1
= an-1 + 2an-2

Register to reply

Related Discussions
Is y'(x) acceptable notation? Calculus & Beyond Homework 5
Is this an acceptable proof? Calculus & Beyond Homework 4
Is 2.02% error acceptable? Introductory Physics Homework 4
is this acceptable Calculus & Beyond Homework 4
relation to Non-Recursive formulas for K(n) and K(2n) Linear & Abstract Algebra 0