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A210887 Number of days after Mar 01 00 such that the date written in the format DD.MM.YY is palindromic.

%I A210887 #24 Feb 03 2021 23:07:45
%S A210887 619,994,1369,3897,4272,4648,7551,7926,8301,11204,11579,11955,14858,
%T A210887 15233,15608,18511,18886,19262,22165,22540,22915,25818,26193,26569,
%U A210887 29472,29847,30222,33125,33500,33876
%N A210887 Number of days after Mar 01 00 such that the date written in the format DD.MM.YY is palindromic.
%C A210887 There are exactly 30 such palindromic dates between Jan 01 00 and Dec 31 99 (see b-file for the complete list).
%C A210887 See A210888 for the corresponding dates.
%C A210887 The reference date Mar 01 00 makes sense, since this result in a sequence which is independent from the leap year / non-leap year property of the reference year "00".
%H A210887 Hieronymus Fischer, <a href="/A210887/b210887.txt">Table of n, a(n) for n = 1..30</a>
%H A210887 <a href="/index/Rec#order_07">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,1,-1).
%F A210887 From _Chai Wah Wu_, Feb 03 2021: (Start)
%F A210887 a(n) = a(n-1) + a(n-6) - a(n-7) for n > 10.
%F A210887 G.f.: x*(375*x^9 + 2284*x^6 + 376*x^5 + 375*x^4 + 2528*x^3 + 375*x^2 + 375*x + 619)/(x^7 - x^6 - x + 1). (End)
%e A210887 The first palindromic date in DD.MM.YY format after "Jan 01 00" is A210888(1)=101101 (="10.11.01"= "Nov 10 01" = "Mar 01 00" + 619 days);
%e A210887 The sixth palindromic date in DD.MM.YY format after "Jan 01 00" is A210888(6)=211112 (="21.11.12"= "Nov 21 12" = "Mar 01 00" + 4648 days).
%e A210887 The last (30th) palindromic date in DD.MM.YY format after "Jan 01 00" is A210888(30)=291192 (="29.11.92"= "Nov 29 92" = "Mar 01 00" + 33876 days).
%Y A210887 Cf. A210883-A210886, A210888-A210895, A106605, A107273, A107275.
%K A210887 nonn,base
%O A210887 1,1
%A A210887 _Hieronymus Fischer_, Apr 01 2012