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 A258016 #11 May 05 2022 12:32:52 %S A258016 19,39,61,81,103,123,145,165,187,207,229,249,271,291,313,333,355,375, %T A258016 397,417,439,459,481,501,523,543,565,585,607,627,649,669,691,711,733, %U A258016 753,775,795,817,837,859,879,901,921,943,963,985,1005,1027,1047,1069,1089,1111,1131,1153,1173,1195,1215,1237,1257,1279,1299,1321,1341,1363,1383,1405 %N A258016 Unlucky numbers removed at the stage three of Lucky sieve. %C A258016 Numbers congruent to 19 or 39 modulo 42. - _Jianing Song_, Apr 27 2022 %H A258016 Antti Karttunen, <a href="/A258016/b258016.txt">Table of n, a(n) for n = 1..10000</a> %H A258016 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (1,1,-1) %F A258016 a(n) = A047241(7*n). %F A258016 a(n) = A260436(A255413(1+n)). %F A258016 From _Jianing Song_, Apr 27 2022: (Start) %F A258016 a(n) = a(n-2) + 42. %F A258016 a(n) = a(n-1) + a(n-2) - a(n-3). %F A258016 G.f.: (19*x+20*x^2+3*x^3)/(1-x-x^2+x^3). %F A258016 E.g.f.: 3 + (21*x-3)*cosh(x) + (21*x-2)*sinh(x). (End) %o A258016 (Scheme, two alternatives) %o A258016 (define (A258016 n) (A047241 (* n 7))) %o A258016 (define (A258016 n) (A255543bi 3 n)) ;; Code for A255543bi given in A255543. %Y A258016 Row 3 of A255543. Every seventh term of A047241. %Y A258016 Cf. also A258011. %K A258016 nonn,easy %O A258016 1,1 %A A258016 _Antti Karttunen_, Jul 27 2015