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A147845
Odd positive integers a(n) such that for every odd integer m>=7 there exists a unique representation of the form m=a(p)+2a(q)+4a(r)
0
1, 3, 17, 19, 129, 131, 145, 147, 1025, 1027, 1041, 1043, 1153, 1155, 1169, 1171, 8193, 8195, 8209, 8211, 8321, 8323, 8337, 8339, 9217, 9219, 9233, 9235, 9345, 9347, 9361, 9363, 65537, 65539, 65553, 65555
OFFSET
1,2
COMMENTS
Since, e.g., 27=17+2*3+4*1 and 17=a(3),3=a(2),1=a(1), then 27 has "coordinates" (3,2,1). Thus we have a one-to-one map of odd integers >=7 to the positive lattice points in the three-dimensional space.
FORMULA
a(n)=2A033045(n-1)+1
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Nov 15 2008
STATUS
approved