cp's OEIS Frontend

A084252 A measure of how close r^n is to an integer where r is the real root of x^3-x-1, i.e.. r = (1/2 + sqrt(23/108))^(1/3) + (1/2 - sqrt(23/108))^(1/3) = 1.3247.... (Higher absolute value of a(n) means closer, negative means less than closest integer.)

%I A084252 #8 Jul 29 2017 19:26:43
%S A084252 3,-4,3,13,13,2,6,2,-2,-3,21,5,-3,4,-10,-18,7,-6,10,-139,-16,11,-14,
%T A084252 39,54,-23,23,-39,3479,53,-40,52,-158,-165,78,-81,148,2429,-177,140,
%U A084252 -191,657,517,-269,289,-563,-3923,595,-492,702,-2833,-1645,933,-1041,2156,9021,-2012,1740,-2590,12872,5304,-3242,3756
%N A084252 A measure of how close r^n is to an integer where r is the real root of x^3-x-1, i.e.. r = (1/2 + sqrt(23/108))^(1/3) + (1/2 - sqrt(23/108))^(1/3) = 1.3247.... (Higher absolute value of a(n) means closer, negative means less than closest integer.)
%F A084252 a(n) = round(1/(r^n - round(r^n))).
%e A084252 a(4)=13 since r^4 = 3.0795956..., 1/(3.0795956...-round(3.0795956...)) = 1/0.0795956... = 12.5635... and round(12.5635...) = 13.
%Y A084252 Cf. A056581, A060006.
%Y A084252 Positive values when n is in A051016 and negative when n is in A051017.
%K A084252 sign
%O A084252 1,1
%A A084252 _Henry Bottomley_, May 22 2003