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 A143995 #23 Jul 26 2023 20:35:56
%S A143995 1776,1816,1844,1872,1912,1940,1968,1996,2024,2052,2080,2120,2148,
%T A143995 2176,2216,2244,2272,2312,2340,2368,2396,2424,2452,2480,2520,2548,
%U A143995 2576,2616,2644,2672,2712,2740,2768,2796,2824,2852,2880,2920,2948,2976,3016,3044
%N A143995 Years in which there are five Thursdays in the month of February, in the Gregorian calendar.
%H A143995 <a href="/index/Ca#calendar">Index entries for sequences related to calendars</a>
%H A143995 <a href="/index/Rec#order_14">Index entries for linear recurrences with constant coefficients</a>, signature (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1).
%p A143995 A143995 := proc(n) nper := (n-1) mod 13 ; floor((n-1)/13)*400+op(1+nper , [1776, 1816, 1844, 1872, 1912, 1940, 1968, 1996, 2024, 2052, 2080, 2120, 2148] ) ; end proc: seq(A143995(n), n=1..80) ; # _R. J. Mathar_, Mar 29 2010
%t A143995 (* Needs Mma version >= 9.0 *)
%t A143995 okQ[y_] := LeapYearQ[{y}] && DayName[{y, 2, 1}] == Thursday;
%t A143995 Select[Range[1752, 3051, 4], okQ] (* _Jean-François Alcover_, Mar 27 2020 *)
%Y A143995 Cf. A119406 (Sun), A135795 (Mon), A143994 (Tue), A141039 (Wed), A141287 (Fri), A176478 (Sat).
%K A143995 nonn
%O A143995 1,1
%A A143995 _J. Lowell_, Sep 07 2008
%E A143995 More terms from _R. J. Mathar_, Mar 29 2010