A111729 Historical progression of years from the song "In The Year 2525" by Denny Zager and Rick Evans.

2525, 3535, 4545, 5555, 6565, 7510, 8510, 9595, 2525

Offset

1,1

Comments

Sequence is potentially cyclic. #1 Billboard hit 1969. Last "2525" added because first verse repeats at the end. Note that it also begins to transition into the second verse again after this in some editions, causing "3535" to be faintly audible. The lyrics of the song also imply the sequence is theoretically cyclic and recurring, with the final 2525 being the beginning of the second iteration.

Links

Table of n, a(n) for n=1..9.

Wikipedia, Zager and Evans.

Wikipedia, In The Year 2525.

Index entries for sequences related to songs

Formula

for n < 6 or n=8, a(n) = 101*(10n+15). For n=6 or 7, a(n) is irregular, and is equal to 101*(10n+15) with the exception that the final two digits are fixed at 10. Assuming the cyclic sequence, for n > 8, a(n) = f(n mod 8), with the exception that when n mod 8 = 0, take a(n) = n(8) = 9595.

Example

The opening lyric is "In the year 2525/if man is still alive/if woman can survive/they may find..." hence a(1)=2525.

Crossrefs

Sequence in context: A031984 A045213 A251918 * A252288 A268332 A369521

Adjacent sequences: A111726 A111727 A111728 * A111730 A111731 A111732

Keyword

nonn,less

Author

Jeff Cohen (jcohen(AT)cpan.org), Nov 18 2005

Extensions

a(9)=2525 and formula added by Gregory Koch, Mar 05 2011

Status

approved