[seqfan] Re: Year 2012 per the OEIS

Veikko Pohjola veikko at nordem.fi
Mon Jan 2 09:25:04 CET 2012


Here is one more sequence dedicated to the year 2012 (not in OEIS):
3248282, 21778346, 48245402, 61326182, 63321086, 71585642, 76337102, 79990346, 80378966, ...

It is based on my conjecture: For every natural number k there are infinitely many semiprime pairs sp and sp' both sandwiched between semiprimes such that sp' - sp = 4k. 

For k=503, the difference between the middles of the adjacent semiprime triples is 2012, and the first pair of the sequence is thus {{3248281, 3248282, 3248283},{3250293, 3250294, 3250295}}.

Happy New  Year,

Veikko

----- Original Message ----- 
From: "Marc LeBrun" <mlb at well.com>
To: "Sequence Fanatics Discussion list" <seqfan at list.seqfan.eu>
Sent: Saturday, December 31, 2011 7:56 PM
Subject: [seqfan] Year 2012 per the OEIS


> Searching on just [2012] in the OEIS returns 13 pages of results--too many
> for me to sift for pearls right now.  But [year 2012] returns just a single
> page, which includes the following sequences:
> 
> A141039 Years in which there are five Wednesdays in the month of February.
> [next is 2040]
> 
> A190653 Years with exactly three "Friday the 13ths", starting from 1901.
> [next is 2015]
> 
> A171467 Years in which a transit of Venus (as seen from Earth) took place or
> is expected to occur, according to the catalog by Fred Espenak.  [next is
> 2117]
> 
> A125680 Blue moon years > 2000.  [next is 2015]
> 
> A162244 Years in which January first falls on a Sunday (since 2001) [next is
> 2017]
> 
> Happy 2012!
> 
> 
> 
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>


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