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A109571
Prague bus clock sequence #2.
1
1, 1, 8, 1, 1, 8, 1, 1, 28, 1, 9, 1, 1, 8, 1, 1, 8, 1, 1, 28, 1, 9, 1, 1, 8, 1, 1, 8, 1, 1, 28, 1, 129, 1, 1, 8, 1, 1, 8, 1, 1, 28, 1, 249, 1, 1, 8, 1, 1, 8, 1, 1, 28, 1, 9, 1, 1, 8, 1, 1, 8, 1, 1, 28, 1, 9, 1, 1, 8, 1, 8, 1, 1, 28, 1, 129, 1, 1, 8, 1, 1, 8, 1, 1, 28, 1, 249, 1, 1, 8, 1, 1, 8, 1, 1, 28, 1, 9
OFFSET
1,3
COMMENTS
Start a digital clock at midnight; you read 00:00 (hours and minutes). Wait for 1 minute and read 00:01; if you look at 00:01 in a mirror, you'll see 10:00, which is a sound time on such a clock; wait for another minute and read 00:02; this gives the "mirror time" 20:00, which is sound; you must wait now for 8 minutes before seeing another sound "mirror time": 00:10 gives 01:00; etc. Successive waiting times form the sequence. The "mirror digit transform" is: 0->0, 1->1, 2->5, 5->2 and 8->8. "8" can't be used here and "5" must be carefully placed.
EXAMPLE
Successive number of minutes one has to wait, starting at midnight, to read a sound "mirror" time on a digital clock.
CROSSREFS
Sequence in context: A248581 A178163 A197110 * A366494 A133823 A168643
KEYWORD
base,easy,fini,nonn
AUTHOR
Eric Angelini and others, Aug 30 2005
STATUS
approved