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 A173693 a(n) = ceiling(A107293(n)/2). 1
 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 5, 7, 10, 14, 20, 28, 41, 59, 85, 122, 176, 254, 367, 529, 764, 1102, 1591, 2296, 3313, 4782, 6901, 9960, 14375, 20747, 29944, 43217, 62373, 90021, 129925, 187516, 270636, 390601, 563742, 813631, 1174288, 1694813, 2446070 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,9 LINKS FORMULA a(n) = A107293(n) - floor(A107293(n)/2) = ceiling(A107293(n)/2). Conjecture: a(n) = a(n-1) + a(n-2) - a(n-3) + a(n-5) + a(n-31) - a(n-32) - a(n-33) + a(n-34) - a(n-36). - R. J. Mathar, Feb 18 2016 MAPLE A107293 := proc(n)     option remember;     if n <=4 then         op(n+1, [0, 0, 0, 0, 1]) ;     else         procname(n-1)+procname(n-2)-procname(n-3)+procname(n-5) ;     end if; end proc: A173693 := proc(n)     ceil(A107293(n)/2) ; end proc: # R. J. Mathar, Feb 18 2016 MATHEMATICA M = {{0, 1, 0, 0, 0}, {0, 0, 1, 0, 0}, {0, 0, 0, 1, 0}, {0, 0, 0, 0, 1}, {1, 0, -1, 1, 1}} v[0] = {0, 0, 0, 0, 1} v[n_] := v[n] = M.v[n - 1] Table[v[n][[1]] - Floor[v[n][[1]]/2], {n, 0, 30}] CROSSREFS Cf. A107293. Sequence in context: A190660 A180158 A320689 * A058278 A097333 A001083 Adjacent sequences:  A173690 A173691 A173692 * A173694 A173695 A173696 KEYWORD nonn,easy AUTHOR Roger L. Bagula, Nov 25 2010 STATUS approved

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Last modified December 12 20:12 EST 2019. Contains 329961 sequences. (Running on oeis4.)