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 A260440 #13 May 05 2022 12:33:01
%S A260440 27,57,91,121,153,183,217,247,279,309,343,373,405,435,469,499,531,561,
%T A260440 595,625,657,687,721,751,783,813,847,877,909,939,973,1003,1035,1065,
%U A260440 1099,1129,1161,1191,1225,1255,1287,1317,1351,1381,1413,1443,1477,1507,1539,1569,1603,1633,1665,1695,1729,1759,1791,1821,1855,1885,1917,1947,1981,2011
%N A260440 Unlucky numbers removed at the stage four of Lucky sieve.
%C A260440 Numbers congruent to {27, 57, 91, 121} modulo 126. - _Jianing Song_, Apr 27 2022
%H A260440 Antti Karttunen, <a href="/A260440/b260440.txt">Table of n, a(n) for n = 1..10000</a>
%H A260440 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,1,-1)
%F A260440 a(n) = A258011(9*n).
%F A260440 a(n) = A260436(A255414(1+n)).
%F A260440 From _Jianing Song_, Apr 27 2022: (Start)
%F A260440 a(n) = a(n-4) + 126.
%F A260440 a(n) = a(n-1) + a(n-4) - a(n-5).
%F A260440 G.f.: (27*x+30*x^2+34*x^3+30*x^4+5*x^5)/(1-x-x^4+x^5).
%F A260440 E.g.f: 1/2*(10 + cos(x) - sin(x) + (63*x-11)*cosh(x) + (63*x-8)*sinh(x)). (End)
%o A260440 (Scheme, two alternatives)
%o A260440 (define (A260440 n) (A258011 (* 9 n)))
%o A260440 (define (A260440 n) (A255543bi 4 n)) ;; Code for A255543bi given in A255543.
%Y A260440 Row 4 of A255543. Every ninth term of A258011.
%K A260440 nonn,easy
%O A260440 1,1
%A A260440 _Antti Karttunen_, Jul 27 2015