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A051950
Differences between values of tau(n) (A000005): a(n) = tau(n)-tau(n-1).
28
1, 0, 1, -1, 2, -2, 2, -1, 1, -2, 4, -4, 2, 0, 1, -3, 4, -4, 4, -2, 0, -2, 6, -5, 1, 0, 2, -4, 6, -6, 4, -2, 0, 0, 5, -7, 2, 0, 4, -6, 6, -6, 4, 0, -2, -2, 8, -7, 3, -2, 2, -4, 6, -4, 4, -4, 0, -2, 10, -10, 2, 2, 1, -3, 4, -6, 4, -2, 4, -6, 10, -10, 2, 2, 0, -2, 4, -6, 8, -5, -1, -2, 10, -8, 0, 0, 4, -6, 10
OFFSET
2,5
LINKS
N. J. A. Sloane, Table of n, a(n) for n = 2..20000 [First 10000 terms from T. D. Noe]
FORMULA
G.f.: (1-x)*sum(k >= 1, x^k/(1-x^k)). - Benoit Cloitre, Apr 24 2003
MATHEMATICA
Differences[DivisorSigma[0, Range[100]]] (* Alonso del Arte, Oct 14 2013, based on T. D. Noe's program for A182394 *)
PROG
(Haskell)
a051950 n = a051950_list !! n
a051950_list = 1 : zipWith (-) (tail a000005_list) a000005_list
-- Reinhard Zumkeller, Feb 04 2013
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Asher Auel, Dec 16 1999
EXTENSIONS
Edited (and offset corrected) by N. J. A. Sloane, Oct 05 2017
STATUS
approved