[seqfan] Help with posting comment for partition numbers
Bob Selcoe
rselcoe at entouchonline.net
Fri Aug 22 01:49:09 CEST 2014
Hi,
Hoping for a little assistance before offering a comment on A000041 (partition numbers). My purpose is to show (IMHO) a simple process to generate multiple recurrence equations which solve A000041(n).
Here's what I intend to post. I think this is clear enough (if not, all constructive criticism is welcome):
(Start)
Referring to the equations f(k) in sequence A026794: a(n) = 1 + sum{k=1..k} f(k), when k+1<=n<=2k+1.
For example, k=3: f(1) = a(n-1); f(2) = a(n-2) - a(n-3); f(3) = a(n-3) - a(n-4) - a(n-5) + a(n-6). Therefore, when 4<=n<=7: a(n) = 1 + a(n-1) + a(n-2) - a(n-4) - a(n-5) + a(n-6) .
These equations solve a(n) when floor(n/2)<=k<=n-1; therefore, the number of equations which solve a(n) using this method is ceiling(n/2). For example, a(7)=15 is solved by four equations: 1 + sum_{k=1..k} f(k), when 3<=k<=6. (End)
Does this look OK? Appropriate to post in A000041 rather than A026794?
Thanks in advance for any assistance,
Bob Selcoe
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