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A174683 Denominator of 1/16 - 1/n^2. 2
0, 16, 16, 144, 16, 400, 144, 784, 64, 1296, 400, 1936, 18, 2704, 784, 3600, 256, 4624, 1296, 5776, 50, 7056, 1936, 8464, 576, 10000, 2704, 11664, 49, 13456, 3600, 15376, 1024, 17424, 4624, 19600, 81, 21904, 5776, 24336, 1600, 26896, 7056, 29584, 242, 32400, 8464, 35344, 2304, 38416 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
The value of a(n)=0 is substituted at the pole n=0.
Extends the Bracket spectrum to negative quantum numbers in the fashion of A061038 (1/4-1/n^2) and A181759 (1/9-1/n^2).
LINKS
FORMULA
a(n) = A061042(n), n>=4.
a(n) = LCM[n^2 - 16, 16*n^2]/(n^2 - 16), for n>=5. - G. C. Greubel, Sep 16 2018
MATHEMATICA
Table[If[n == 0, 0, If[n == 4, 16, Denominator[(n^2 - 16)/(4*n)^2]]], {n, 0, 100}] (* G. C. Greubel, Sep 16 2018 *)
PROG
(PARI) for(n=0, 100, print1(if(n==0, 0, if(n==4, 16, denominator((n^2 - 16)/(4*n)^2))), ", ")) \\ G. C. Greubel, Sep 16 2018
CROSSREFS
Cf A174680 (numerators).
Sequence in context: A226068 A087970 A230977 * A174994 A175971 A165837
KEYWORD
nonn,easy,frac
AUTHOR
Paul Curtz, Nov 30 2010
EXTENSIONS
Removed a(-4)-a(-1) since a(-n)=a(n) by G. C. Greubel, Sep 16 2018
STATUS
approved

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Last modified March 2 21:08 EST 2024. Contains 370498 sequences. (Running on oeis4.)