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%I #15 Aug 06 2017 22:26:55
%S 1,1,1,0,2,-2,1,0,4,2,-2,-5,0,-2,6,2,8,-8,-2,4,-8,2,8,4,-6,-1,0,8,-4,
%T -2,-4,4,0,4,6,-4,-8,-4,12,2,14,-10,6,-10,3,0,-10,4,8,-4,4,12,-14,10,
%U -1,12,10,-6,-8,-8,-2,6,0,8,-12,2,-10,-14,8,0,-4,20,2,-4,-4,12,10,-14,-7,-8
%N a(n) = d(p(n)+1) - d(p(n)-1), where d(m) = the number of divisors of m, p(n) = the n-th prime.
%H Harvey P. Dale, <a href="/A145337/b145337.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = A008329(n) - A008328(n). - _R. J. Mathar_, Oct 10 2008
%p A000005 := proc(n) numtheory[tau](n) ; end:
%p A008328 := proc(n) A000005(ithprime(n)-1) ; end:
%p A008329 := proc(n) A000005(ithprime(n)+1) ; end:
%p A145337 := proc(n) A008329(n)-A008328(n) ; end: # _R. J. Mathar_, Oct 10 2008
%t DivisorSigma[0,#+1]-DivisorSigma[0,#-1]&/@Prime[Range[80]] (* _Harvey P. Dale_, Nov 01 2011 *)
%Y Cf. A008328, A008329, A067889, A103664, A103665, A145338.
%K sign
%O 0,5
%A _Leroy Quet_, Oct 08 2008
%E More terms from _R. J. Mathar_ and _Ray Chandler_, Oct 10 2008
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