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 A275068 #15 Aug 20 2025 10:33:56
%S A275068 1,5,11,19,29,31,41,55,59,61,71,79,89,95,101,109,131,139,145,149,151,
%T A275068 155,179,181,191,199,205,209,211,229,239,241,251,269,271,281,295,305,
%U A275068 311,319,331,341,349,355,359,379,389,395,401,409,419,421,431,439,445
%N A275068 Squarefree numbers in A022344.
%C A275068 The final digit of every number is 1, 5, or 9. As a set, A022344 consists of the numbers m*F^2, where m is in (1,5,11,19,...) and F is a Fibonacci number.
%C A275068 The restriction here to squarefree numbers excludes any of Wechsler's J determinants that derive from rows of the Wythoff array where all terms share a common factor, but there are also nonsquarefree numbers that are determinants of other rows: for example, 121 is the J determinant of row 45 (..., 3, 13, 16, 29, 45, 74, 119, 193, ...). Compare with A089270, which includes 121 and other such numbers. - _Peter Munn_, Aug 20 2025
%H A275068 Clark Kimberling, <a href="/A275068/b275068.txt">Table of n, a(n) for n = 0..1000</a>
%e A275068 A022344 = (1,5,4,9,16,11,19,11,20,31,19,31,45,29,... ), and deletion of 4,9,16,20, ... leaves (1,5,11,19,29,31,...).
%t A275068 g = GoldenRatio; a[n_] := Floor[(n + 1)*g]^2 - n*Floor[(n + 1)*g] - n^2;
%t A275068 u = Table[a[n], {n, 0, 200}] (* A022344 *)
%t A275068 Union[Select[u, SquareFreeQ[#] &]] (* A275068 *)
%Y A275068 Cf. A000045, A022344, A035513, A089270.
%K A275068 nonn,easy
%O A275068 0,2
%A A275068 _Clark Kimberling_, Jul 15 2016