OFFSET
1,1
COMMENTS
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
Curtis J. Humphreys, The Sixth Series in the Hydrogen Spectrum, Journal of the Optical Society of America, 1952, 42, p. 432.
EXAMPLE
The fractions are -35/36, -2/9, -1/12, -5/144, -11/900, 0, 13/1764, 7/576, 5/324, 4/225, 85/4356, 1/48, 133/6084, 10/441, 7/300, 55/2304, 253/10404, 2/81, 325/12996, ...
MATHEMATICA
Numerator[(1/36-1/Range[100]^2)] (* Harvey P. Dale, Mar 17 2013 *)
PROG
(Haskell)
import Data.Ratio ((%), numerator)
a061045 = numerator . (1 % 36 -) . recip . (^ 2) . fromIntegral
-- Reinhard Zumkeller, Jan 06 2014
(Magma) [Numerator(1/6^2 -1/n^2): n in [1..80]]; // G. C. Greubel, Feb 24 2023
(SageMath)
def A061045(n): return ((n^2-36)/(6*n)^2).numerator()
[A061045(n) for n in range(1, 81)] # G. C. Greubel, Feb 24 2023
CROSSREFS
KEYWORD
sign,frac
AUTHOR
N. J. A. Sloane, May 26 2001
STATUS
approved