login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A207982 Least m>1 such that all central binomial coefficients C(2k,k), k<=n, are pairwise not congruent mod m. 11

%I #17 Sep 10 2018 13:37:13

%S 2,3,5,11,11,11,23,23,23,31,43,43,43,43,59,59,59,59,107,149,151,151,

%T 151,151,163,163,163,163,163,163,163,163,163,277,277,277,277,401,401,

%U 457,457,457,457,457,457,457,479,479,479,479,479,479,479,479,479,479

%N Least m>1 such that all central binomial coefficients C(2k,k), k<=n, are pairwise not congruent mod m.

%H Chai Wah Wu, <a href="/A207982/b207982.txt">Table of n, a(n) for n = 1..5000</a>

%H Z. W. Sun, <a href="https://listserv.nodak.edu/cgi-bin/wa.exe?A2=NMBRTHRY;df748f41.1202">A function taking only prime values</a>, Number Theory list, Feb 21 2012

%o (PARI) m=2; for(n=1,99, forstep(nn=n,2,-1,for(k=1,nn-1,(binomial(nn*2,nn)-binomial(2*k,k))%m&next; m++; nn=n+1;next(2))); print1(m", "))

%K nonn

%O 1,1

%A _M. F. Hasler_, Feb 22 2012

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 23 20:33 EDT 2024. Contains 371916 sequences. (Running on oeis4.)