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%I #21 May 28 2017 07:28:17
%S 0,0,0,1,0,2,0,1,1,2,0,3,0,2,2,2,0,3,0,3,2,2,0,5,1,2,1,3,0,6,0,2,2,2,
%T 2,6,0,2,2,5,0,6,0,3,3,2,0,6,1,3,2,3,0,5,2,5,2,2,0,10,0,2,3,3,2,6,0,3,
%U 2,6,0,8,0,2,3,3,2,6,0,6,2,2,0,10,2,2
%N The number of arcs from odd to even level vertices in divisor lattice D(n).
%H R. J. Mathar, <a href="/A238951/b238951.txt">Table of n, a(n) for n = 1..1000</a>
%H S.-H. Cha, E. G. DuCasse, and L. V. Quintas, <a href="http://arxiv.org/abs/1405.5283">Graph Invariants Based on the Divides Relation and Ordered by Prime Signatures</a>, arXiv:1405.5283 [math.NT], 2014 (see 12th line in Table 1).
%F a(n) = A062799(n) - A238950(n) = floor(A062799(n)/2). [Cha eqs. (2.34), (2.37)]
%p read("transforms"):
%p omega := [seq(A001221(n), n=1..1000)] ;
%p ones := [seq(1,n=1..1000)] ;
%p a062799 := DIRICHLET(ones,omega) ;
%p for n from 1 do
%p a238951 := floor(op(n,a062799)/2) ;
%p printf("%d %d\n",n,a238951) ;
%p end do: # _R. J. Mathar_, May 28 2017
%Y Cf. A056924, A062799, A238950.
%K nonn
%O 1,6
%A _Sung-Hyuk Cha_, Mar 07 2014
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