# Math Help - sequences by primitive recursive rules?

1. ## sequences by primitive recursive rules?

a0 = 100
an+1 = G(an,n) where G(x,n) = x-n

what are the first four sequences?

i realize a0=100
and an(a0) +1 = 101
but i do not understand the G(an,n) part or the G(x,n) parts........

can someone explain how i get the answer without telling me, as i want to know how its done...thank you

2. Originally Posted by Apple8736
a0 = 100
an+1 = G(an,n) where G(x,n) = x-n

what are the first four sequences?

i realize a0=100
and an(a0) +1 = 101
but i do not understand the G(an,n) part or the G(x,n) parts........

can someone explain how i get the answer without telling me, as i want to know how its done...thank you
This looks to me like...

$a_0=100$
$a_{n+1}=a_n-n$

$a_1=a_0-0=100-0=100$
$a_2=a_1-1=100-1=99$