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A005057
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a(n) = 5^n - 2^n.
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15
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0, 3, 21, 117, 609, 3093, 15561, 77997, 390369, 1952613, 9764601, 48826077, 244136529, 1220694933, 6103499241, 30517545357, 152587825089, 762939322053, 3814697003481, 19073485803837, 95367430592049, 476837156105973, 2384185786821321, 11920928946689517
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OFFSET
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0,2
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COMMENTS
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REFERENCES
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P. P. Patwardhan, Discrete Structures, Technical Publications Pune, 2009 (first ed.), Section 4.27.1.2, p. 110 (Example 4.44-i).
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LINKS
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FORMULA
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G.f.: 1/(1-5*x)-1/(1-2*x);
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MAPLE
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MATHEMATICA
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PROG
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(Magma) [ 5^n-2^n: n in [0..24] ];
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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