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A061043 Numerator of 1/25 - 1/n^2. 15
0, 11, 24, 39, 56, 3, 96, 119, 144, 171, 8, 231, 264, 299, 336, 3, 416, 459, 504, 551, 24, 651, 704, 759, 816, 7, 936, 999, 1064, 1131, 48, 1271, 1344, 1419, 1496, 63, 1656, 1739, 1824, 1911, 16, 2091, 2184, 2279, 2376, 99, 2576, 2679, 2784 (list; graph; refs; listen; history; text; internal format)
OFFSET

5,2

COMMENTS

From Pfund spectrum of hydrogen. Wavelengths in hydrogen spectrum are given by Rydberg's formula 1/wavelength = constant*(1/m^2 - 1/n^2).

a(n)=(n+5)^2-25=n*(n+10) except a(5p) p pos. Second (with m=5) of this kind after AO61039,Paschen (m=3) and before A061047,Hansen-Strong (m=7). For the fourth,what is the value of m in 1/m^2-1/n^2 ? m=9? [From Paul Curtz, Nov 01 2008]

REFERENCES

J. E. Brady and G. E. Humiston, General Chemistry, 3rd. ed., Wiley; p. 78.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 5..10000

J. J. O'Connor and E. F. Robertson, Johannes Robert Rydberg

Eric Weisstein's World of Physics, Balmer Formula

MATHEMATICA

Numerator[1/25-1/Range[5, 60]^2] (* Harvey P. Dale, Jan 28 2013 *)

PROG

(Haskell)

import Data.Ratio ((%), numerator)

a061043 = numerator . (1 % 25 -) . recip . (^ 2) . fromIntegral

-- Reinhard Zumkeller, Jan 06 2014

CROSSREFS

Cf. A061035-A061050.

Sequence in context: A269100 A213062 A157756 * A098603 A274620 A053061

Adjacent sequences:  A061040 A061041 A061042 * A061044 A061045 A061046

KEYWORD

nonn,frac,nice

AUTHOR

N. J. A. Sloane, May 26 2001

STATUS

approved

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Last modified December 3 07:27 EST 2016. Contains 278698 sequences.