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.

A216071 Brocard's problem: positive integers m such that m^2 = n! + 1 for some n.

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%I A216071 #23 Sep 16 2022 12:52:36
%S A216071 5,11,71
%N A216071 Brocard's problem: positive integers m such that m^2 = n! + 1 for some n.
%C A216071 See A085692 and A146968 for links, references and comments. - _M. F. Hasler_, Nov 20 2018
%H A216071 Wikipedia, <a href="https://en.wikipedia.org/wiki/Brocard%27s_problem">Brocard's problem</a>
%F A216071 a(n) = A000196(A085692(n)) = A000196(A038507(A146968(n))) where A000196 = sqrt and A038507(n) = n! + 1. - _M. F. Hasler_, Nov 20 2018
%t A216071 Sqrt[#!+1]&/@Select[Range[1000],IntegerQ[Sqrt[#!+1]]&] (* _Harvey P. Dale_, Sep 29 2012 *)
%o A216071 (PARI) apply( sqrtint, A085692) \\ _M. F. Hasler_, Nov 20 2018
%o A216071 (PARI) select( is_A216071(m)=m^2==A084558(m^2)!+1, [0..99]) \\ _M. F. Hasler_, Nov 20 2018
%Y A216071 A085692, A146968, A216071 are all essentially the same sequence. - _N. J. A. Sloane_, Sep 01 2012
%K A216071 nonn,hard,bref
%O A216071 1,1
%A A216071 _V. Raman_, Sep 01 2012