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A082567
Palindromic time display in hours, minutes, seconds on a six spaced 24-hour digital clock, using hours 1-24.
2
10001, 10101, 10201, 10301, 10401, 10501, 10601, 10701, 10801, 10901, 11011, 11111, 11211, 11311, 11411, 11511, 11611, 11711, 11811, 11911, 12021, 12121, 12221, 12321, 12421, 12521, 12621, 12721, 12821, 12921, 13031, 13131, 13231, 13331, 13431, 13531
OFFSET
1,1
COMMENTS
Leading zeros for the hours are ignored, so entries of this sequence may have 5 or 6 digits. Sequence has 606 entries. Greatest leap occurs between the successive terms a(576) = 155551 and a(577) = 200002; that is, between 15h55m51s and 20h00m02s.
See A222620 for a version of this sequence using hours 0-23 instead of 1-24.
LINKS
Nathaniel Johnston, Table of n, a(n) for n = 1..606 (full sequence)
EXAMPLE
40704 actually stands for 4:07:04, i.e., 4h07m04s. Similarly, 123321 stands for 12:33:21, i.e., 12h33m21s.
MAPLE
for h from 1 to 24 do for m from 0 to 59 do for s from 0 to 59 do t:=10000*h+100*m+s: d:=convert(t, base, 10): n:=nops(d): if(d[1]=d[n] and d[2]=d[n-1] and d[3]=d[n-2])then printf("%d, ", t): fi: od: od: od: # Nathaniel Johnston, May 17 2011
MATHEMATICA
Select[Table[FromDigits@ Flatten@ Map[PadLeft[IntegerDigits@ #, 2] &, IntegerDigits[n, 60]], {n, 3600, 86400}], PalindromeQ] (* Michael De Vlieger, Aug 15 2017 *)
CROSSREFS
Cf. A222620.
Sequence in context: A291312 A203591 A115850 * A364050 A360574 A330135
KEYWORD
fini,full,base,nonn
AUTHOR
Lekraj Beedassy, May 06 2003
EXTENSIONS
Edited by Nathaniel Johnston, May 17 2011
STATUS
approved