A210890 Dates after Jan 01 00 in chronological order which are palindromic when they are written in the format D.M.YY. The terms are listed as numbers (without the dots).

10101, 10201, 10301, 10401, 10501, 10601, 10701, 10801, 10901, 101101, 20102, 20202, 20302, 20402, 20502, 20602, 20702, 20802, 20902, 201102, 30103, 30303, 30403, 30503, 30603, 30703, 30803, 30903, 301103, 1111, 11111, 11211, 11311, 11411, 11511, 11611, 11711

Offset: 1

Author

Hieronymus Fischer, Apr 01 2012

Keywords

• nonn
• base

Comments

There are exactly 322 such palindromic dates between Mar 1 00 and Dec 31 99 (see b-file for the complete list).

See A210889 for the number of days after 'Mar 1 00' to get such a palindromic date.

The definition is different from A210892 in that the dates are considered as numbers.

Some numbers occur twice since the dates are not unique without the dots. For example, the number 11211 may represent the date 11.2.11 (Feb 11 11) or 1.12.11 (Dec 1 11). The complete list of such dates is 11.1.11, 11.2.11, 1.11.11, 1.12.11, 21.1.12, 21.2.12, 2.11.12, 2.12.12, 31.1.13 and 3.11.13 which correspond to the terms with n=31,32,41,43,45,46,55,57,59 and 65.

Examples

			The first palindromic date in D.M.YY format after 'Jan 01 00' is a(1)=10101 (= '10.1.01' = 'Jan 10 01' = 'Mar 01 00' + A210889(1) days);
The 10th palindromic date in D.M.YY format after 'Jan 01 00' is a(10)=101101 (= '10.11.01' = 'Nov 10 01' = 'Mar 01 00' + A210889(10) days);
The 44th palindromic date in D.M.YY format after 'Jan 01 00' is a(44)=2112 (= '2.1.12' = 'Jan 2 12' = 'Mar 01 00' + A210889(44) days);
The last (322nd) palindromic date in D.M.YY format after 'Jan 01 00' is a(322)=9999 (= '9.9.99' = 'Sep 09 99' = 'Mar 01 00' + A210889(322) days).
		

Links

• Hieronymus Fischer, Table of n, a(n) for n = 1..322

Crossrefs

Cf. A210883-A210889, A210891-A210895, A106605, A107273, A107275.

Formula

a(n) = DMYY_date('Mar 1 00' + A210889(n)).