cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A071855 Numbers n such that A067434(n) = A000720(n) + A000005(n).

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%I A071855 #11 Mar 25 2015 01:21:06
%S A071855 1,37,41,43,47,49,58,65,69,81,85,92,128,130,135,136,154,184,208,220,
%T A071855 228,450,540,840
%N A071855 Numbers n such that A067434(n) = A000720(n) + A000005(n).
%C A071855 No further terms below 143260.
%C A071855 No further terms below 2*10^4. - _Robert G. Wilson v_
%t A071855 Select[ Range[10^3], Length[ FactorInteger[ Binomial[2#, # ]]] == PrimePi[ # ] + DivisorSigma[0, # ] & ]
%o A071855 (PARI) for(n=1,1000,if(omega(binomial(2*n,n))=sum(i=1,n,isprime(i))+numdiv(n),print1(n,",")))
%K A071855 nonn
%O A071855 1,2
%A A071855 _Benoit Cloitre_, Jun 09 2002