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A207079
The only nonunique differences between powers of 3 and 2.
5
1, 5, 7, 13, 23
OFFSET
1,2
COMMENTS
The sequence is finite, this fact is a theorem in [Bennet2004].
1 = 3-2 = 3^2-2^3 = 2^2-3.
5 = 3^2-2^2 = 2^3-3 = 2^5 - 3^3.
7 = 2^4-3^2 = 3^2 - 2.
13 = 2^4-3 = 2^8 - 3^5.
23 = 3^3 - 2^2 = 2^5 - 3^2.
LINKS
M. A. Bennett, Pillai's conjecture revisited, J. Number Theory 98 (2003), 228-235.
Douglas Edward Iannucci, On duplicate representations as 2^x+3^y for nonnegative integers x and y, arXiv:1907.03347 [math.NT], 2019. Mentions this sequence.
FORMULA
A219551(a(n)) > 1. - Jonathan Sondow, Dec 10 2012
CROSSREFS
KEYWORD
nonn,bref,fini,full
AUTHOR
Gottfried Helms, Feb 15 2012
STATUS
approved