login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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). 4
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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.

LINKS

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

FORMULA

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

EXAMPLE

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).

CROSSREFS

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

Sequence in context: A265122 A267146 A043641 * A210892 A258189 A114385

Adjacent sequences:  A210887 A210888 A210889 * A210891 A210892 A210893

KEYWORD

nonn,base

AUTHOR

Hieronymus Fischer, Apr 01 2012

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 21 14:06 EDT 2019. Contains 328300 sequences. (Running on oeis4.)