[seqfan] naive sequence generator

Georgi Guninski guninski at guninski.com
Tue Jan 12 16:47:18 CET 2010


wrote a naive integer sequence generator (basically an expression generator).

online demo supporting OEIS searches is at:
http://stefan.guninski.com/funfu.cgi

the python source (better run it in sage) is at:
http://stefan.guninski.com/funfu.py

some of the less ugly sequences:

f[0]=1,f[n]= (f[n-1]+Sigma[f[n//2]]) 
f[0]=1,f[n]= eulerphi[(Sigma[eulerphi[(n + 1)]]*eulerphi[Sigma[n]])]
f[0]=1,f[n]= (f[n//2]+f[n//2])
f[0]=1,f[n]= Sigma[Sigma[eulerphi[eulerphi[(n + 1)]]]]
f[0]=1,f[n]= (eulerphi[((n+(n + 1))*f[n//2])] // f[n-1]) 
( a // b <=> floor(a/b)
mass generating sequences and searching in local copy of OEIS didn't produce anything reasonable for the limited time i tested.

-- 
joro




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