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.
%I A229466 #21 Jul 28 2025 09:00:09
%S A229466 10,30,70,130,370,430,670,730,970,1030,1270,1570,1630,1930,2230,2770,
%T A229466 2830,3130,3370,3670,3730,3970,4330,4570,4630,4870,5230,5470,5770,
%U A229466 6070,6130,6430,6730,7270,7330,7570,7870,8230,8530,8770,8830,9070,9370,9970
%N A229466 Numbers k such that the period of Fibonacci numbers mod k is 3*(k+10).
%C A229466 Related to Pisano periods. Other than the initial term 10, these are a subset of the terms of A071774 multiplied by 10, where A071774 are numbers m such that Fibonacci numbers mod m = 2*(m+1). All A071774 terms multiplied by 10 have Pisano periods 3*(n+10) or (n+10). This sequence is the 3*(n+10) subset. A229467 is the n+10 subset.
%H A229466 Matthew Goers, <a href="/A229466/b229466.txt">Table of n, a(n) for n = 1..74</a>
%e A229466 The Pisano period of the Fibonacci numbers mod 30 = 120, which is 3*(30+10).
%e A229466 The Pisano period of the Fibonacci numbers mod 1570 = 4740, which is 3*(1570+10).
%t A229466 t = {}; Do[a = {1, 0}; a0 = a; k = 0; While[k++; s = Mod[Plus @@ a, n]; a = RotateLeft[a]; a[[2]] = s; k <= 3*(n + 10) && a != a0]; If[k == 3*(n + 10), AppendTo[t, n]], {n, 2, 10000}]; t (* _T. D. Noe_, Oct 02 2013 *)
%Y A229466 Cf. A000045, A001175, A071774, A229467.
%K A229466 nonn
%O A229466 1,1
%A A229466 _Matthew Goers_, Sep 24 2013