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%I #7 Mar 01 2019 23:33:15
%S 0,2,0,3,-1,3,-1,3,-3,4,-2,5,-1,3,-3,6,-2,4,-3,3,-2,5,-3,7,-4,3,-1,3,
%T -1,9,-7,5,-2,6,-4,4,-4,5,-3,6,-2,6,-4,3,-1,7,-10,8,-1,3,-3,4,-4,8,-4,
%U 6,-2,4,-3,3,-4,12,-7,3,-1,9,-8,8,-4,3,-3,7,-5,6,-3,5,-5,6,-4,9,-4,6,-4,4,-3
%N First differences of A162200.
%C The absolute value of a(n) is also the length of the n-th vertical edge in the graph of the "mountain path" function for prime numbers.
%C See A162200 for the length of the n-th horizontal component.
%H Omar E. Pol, <a href="http://www.polprimos.com/imagenespub/polmpfpn.jpg"> Graph of the mountain path function for prime numbers</a>
%H Omar E. Pol, <a href="http://www.polprimos.com/imagenespub/polmpca1.jpg"> Illustration: The mountain path of the primes</a>
%F From _R. J. Mathar_, Jul 15 2009: (Start)
%F a(n) = A052288(n-1) if n >= 2, n even.
%F a(n) = 2 - A052288(n-1) if n >= 3, n odd. (End)
%p A031131 := proc(n) ithprime(n+2)-ithprime(n) ; end: A052288 := proc(n) A031131(n)/2 ; end: A160173 := proc(n) if n <= 2 then 2*(n-1); elif n mod 2 = 0 then A052288(n-1) ; else 2-A052288(n-1) ; fi; end: seq(A160173(n),n=1..150) ; # _R. J. Mathar_, Jul 15 2009
%Y Cf. A000040, A006005, A008578, A162200, A162202, A162203, A162340, A162341, A162342, A162343, A162344.
%K easy,sign
%O 1,2
%A _Omar E. Pol_, Jun 28 2009
%E Edited by _Omar E. Pol_, Jul 02 2009
%E More terms from _R. J. Mathar_, Jul 15 2009
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