cp's OEIS Frontend

A191909 Decimal expansion of the limit of the square root of the ratio of consecutive Padovan numbers.

%I A191909 #18 Aug 21 2023 11:40:07
%S A191909 8,6,8,8,3,6,9,6,1,8,3,2,7,0,9,3,0,1,8,0,6,5,6,9,9,6,4,1,9,1,0,9,7,2,
%T A191909 2,2,4,7,7,4,6,5,6,6,2,0,1,4,4,9,9,3,1,6,9,2,6,0,8,7,1,9,8,5,6,1,2,6,
%U A191909 0,2,2,0,7,5,2,2,7,7,7,4,1,1,8,1,4,2
%N A191909 Decimal expansion of the limit of the square root of the ratio of consecutive Padovan numbers.
%C A191909 This is the square root of the inverse of the plastic number A060006: 1.32471795724...
%C A191909 This is the positive root of x^6 + x^4 - 1 = 0 and the square root of A075778.
%C A191909 An algebraic integer of degree 6 and minimal polynomial x^6 + x^4 - 1. - _Charles R Greathouse IV_, Apr 21 2016
%H A191909 Wikipedia, <a href="http://en.wikipedia.org/wiki/Plastic_number">Plastic number</a>
%H A191909 <a href="/index/Al#algebraic_06">Index entries for algebraic numbers, degree 6</a>
%e A191909 0.868836961832709301806569964191...
%t A191909 RealDigits[x/.FindRoot[x^6+x^4==1,{x,.8},WorkingPrecision->120]][[1]] (* _Harvey P. Dale_, Jan 17 2014 *)
%o A191909 (PARI) polrootsreal(x^6+x^4-1)[2] \\ _Charles R Greathouse IV_, Apr 21 2016
%Y A191909 Cf. A000931, A060006.
%K A191909 nonn,cons
%O A191909 0,1
%A A191909 _Fabrice Auzanneau_, Jun 19 2011